Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A decreased secretion of arginine vasopressin (AVP) has been implicated in depression. In order to further investigate this hypothesis, we studied the plasma level of the specific peptidergic carrier of AVP, vasopressin neurophysin (hNpI), in 26 depressed inpatients and 16 matched normal controls. On the other hand, AVP has also been involved in the pathophysiology of the cortisol postdexamethasone nonsuppression frequently observed in depression. Therefore, we investigated concomitantly hNpI and cortisol during a dexamethasone (DXM) suppression test. hNpI and cortisol were assessed by radioimmunoassay at 8 AM and 8 PM during 4 consecutive days. From days 2 to 3, 4 mg (DXM) was given orally. hNpI values were not affected by DXM administration. Compared with controls, patients showed higher pre- and post-DXM cortisol values and lower hNpI values. No difference in hNpI values was observed between DXM escapers or nonescapers. Our results are consistent with an impaired AVP secretion in depression and fail to support a role of AVP in the early cortisol escape.
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PMID:Plasmatic vasopressin neurophysin in depression: basic levels and relations with HPA axis. 235 30

We have shown previously that intrathecal administration of substance P to the lower thoracic vertebral level increases sympathetic output and increases the adrenal output of catecholamines. As opioid peptides are co-released with catecholamines from the adrenal medullae, experiments were done to determine whether the intrathecal administration of substance P to the eighth thoracic vertebral level would alter reaction time in the tail-flick test. Intrathecal administration of substance P (6.5 nmoles in artificial cerebrospinal fluid) in the awake restrained rat increased the reaction time at 1 and 6 min after injection to about 130-140% of the preadministration values; reaction time returned to preadministration values by 11 min. Similar administration of cerebrospinal fluid was without effect. Administration of 6.5 nmoles of thyrotropin-releasing hormone or oxytocin, peptides which also increase sympathetic output, failed to mimic the effects of substance P. The substance P-induced increase in reaction time was absent in rats which had been medullectomized and in rats pretreated with naloxone (10 mg/kg). Pretreatment with 10 mg/kg of either phentolamine or the quaternary opiate antagonists, nalorphine methochloride and naloxone methobromide, had no effect on the substance P-induced increase in reaction time. These results suggest that substance P given intrathecally to the eighth thoracic vertebral level may activate spinal sympathetic neurons to the adrenal medullae to cause the release of an opioid into the circulation. This circulating opioid may in turn play a role in the regulation of the tail-flick reflex by a centrally-mediated depression.
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PMID:An adrenal-mediated, naloxone-reversible increase in reaction time in the tail-flick test following intrathecal administration of substance P at the lower thoracic spinal level in the rat. 245 44

We recently reported that acute pharmacologic depression of dopaminergic tone at different times of day unmasks a sex-specific endogenous stimulatory rhythm regulating PRL secretion. The PRL secretory responses of ovariectomized rats to the dopamine antagonist domperidone (DOM) were higher at 0300 and 1700 h than at 1200 h. These are the times during which surges of PRL appear in mated rats. This experimental paradigm was used to investigate the roles of the putative PRL-releasing factors (PRFs) oxytocin (OT), vasoactive intestinal peptide (VIP), and serotonin (5-HT) in this rhythm. The role of OT was studied by infusion of the OT antagonist 1-deamino-2-D-Trp-4-Val-8-Orn-Oxytocin (OT-A, 0.5 microgram/kg min) for 6 h. Two hours after beginning the OT-A infusion DOM was administered, as a single injection of 200 micrograms/kg iv at either 0300, 1200, or 1700 h. Serial blood samples were collected immediately before and 5, 10, 20, 30, 60, 120, 180, and 240 min after DOM administration. Infusion of OT-A attenuated the heightened PRL secretory responses to DOM given at both 0300 and 1700 h but did not affect the response at 1200 h. The role of VIP was studied by infusing the VIP antagonist [D, 4-Cl-Phe6,Leu17] VIP (VIP-A, 0.1 microgram/kg.min) as described above. VIP-A infusion had no effect on the PRL secretory responses to DOM given at 1200 or 1700 h but attenuated the heightened response at 0300 h. In order to study the role of 5-HT in the rhythm, rats were pretreated with p-chlorophenylalanine (250 mg/kg sc) 48 and again 24 h before the experiment. Pretreatment with p-chlorophenylalanine had no effect on the PRL secretory responses to DOM given at 0300 or 1200 h, but it attenuated the augmented PRL secretory response at 1700 h. These data suggest that both VIP and OT act as endogenous PRFs at 0300 h and 5-HT and OT act as PRFs at 1700 h. We propose that VIP and 5-HT are continuously active oscillatory neurotransmitters regulating OT release into pituitary portal blood and that these daily events only eventuate in PRL release when the mating stimulus has release the lactotroph from the inhibitory effects of dopamine.
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PMID:Hypothalamic factors involved in the endogenous stimulatory rhythm regulating prolactin secretion. 252 68

The authors use an intravenous dose of 0.5 g glucose/kg. body weight as a fetal stimulation test in one hundred pregnant patients after the 34th week. Glucose produced a remarkable increase of fetal heart rate variability, as well as an increase in the number of fetal movements and accelerations. Those fetuses lacking reactivity before and after the glucose test presented, in 55.5% of the cases, neonatal depression. This suggests that glucose perinatal surveillance is of utmost importance in these cases. The glucose overload test presents a clear advantage with respect to the oxytocin test, which is the total absence of labor stimulation and this may not be desirable in cases of prematurity or previous uterine scars.
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PMID:[The glucose perfusion test: value in detecting fetal distress]. 277 83

The intrapartum fetal heart rate changes, type of labor, mode of delivery, and neonatal outcome were evaluated in 379 consecutive continuously monitored prolonged pregnancies (greater than 42 weeks by history and early examination). These represent only a fraction of the total prolonged gestation population. There were 56% multiparous women, 33% less than 20 years of age, and 95% with cephalic presentation. Oxytocin was given to 76% (48% induced, 28% enhanced). Delivery was by cesarean section in 13% of patients (9% of induced cases), and 15% had forceps deliveries. Fetal heart rate alterations were observed in high proportion. Cesarean section for cephalopelvic disproportion was indicated in 60% of operations, and 13% of the fetuses weighed greater than 4000 gm. Depression occurred in 15% of infants at 1 minute and in 4% at 5 minutes. Prolonged hospital stay was seen in 9%, and postmaturity syndrome in 19%. There were four perinatal deaths (two corrected). Active induction does not appear to increase the cesarean section rate. The durations of predelivery observation may be longer because the cervices are frequently unripe. There is a high incidence of fetal heart rate alterations. Induction appears justified as an active intervention to prevent some sudden unexplained deaths.
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PMID:Maternal-fetal outcomes in prolonged pregnancy. 280 39

The effect of vasopressin and oxytocin on the dorsal root potentials were studied in isolated spinal cord of 12-16 days old rats. It was shown that both neuropeptides evoked reversible depression of the dorsal root potential induced by stimulation of the neighbouring dorsal root. Application of vasopressin or oxytocin caused the reversible dose-dependent depolarization in the dorsal root. The depolarization was preserved in Ca2+-free manganese-containing solution. Functional significance of presynaptic effects of hypothalamic neuropeptides is discussed.
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PMID:[Effect of vasopressin and oxytocin on the dorsal root potentials of the isolated perfused spinal cord in rat pups]. 285 81

Plasma concentrations of oestrogen-stimulated neurophysin (ESN), prolactin, and growth hormone were measured before and after the first treatment in a course of electroconvulsive therapy (ECT) given to 25 psychiatric patients and during induction of anaesthesia in 9 women undergoing elective cholecystectomy. Prolactin levels rose and growth hormone levels fell during both cholecystectomy and ECT, but ESN levels rose only after ECT. The peak ESN response to ECT was significantly greater (p less than 0.005) in the 16 depressed patients who recovered than in the 9 who did not. All patients in whom plasma ESN concentration increased by more than 100% satisfactorily recovered from their depressive illness. If a 63% increase in ESN concentration is used to classify all subjects, 12% are misclassified by outcome at 2 months. The extent of the ESN response, but not the prolactin or growth hormone responses, correlated with improvement in symptoms measured by Hamilton Rating Scale for Depression and the Montgomery and Asberg Depression Rating Scale.
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PMID:Oestrogen-stimulated neurophysin and outcome after electroconvulsive therapy. 287 18

Serum concentrations of immunoreactive neurophysin (IRN) and vasopressin-associated neurophysin (hNpI) were measured before and after the first treatment in a course of electroencephalographically monitored electroconvulsive therapy (ECT) given to 19 depressed patients. The difference (DIFF) between the serum concentrations of IRN and hNpI is equivalent to the concentration of oxytocin-associated neurophysin. Before ECT the six patients who had a good outcome at 2 months after the course of ECT had a mean serum IRN concentration one-half (p less than 0.05) and a mean serum DIFF concentration one-third (p less than 0.05) that of the 13 patients who had a poor outcome. The increase in serum DIFF concentration (but not IRN or hNpI) after the first ECT correlated with the improvement on the Hamilton Rating Scale for Depression (r = -0.73, p less than 0.005) and the Montgomery and Asberg Depression Rating Scale (r = -0.49, p less than 0.05). The peak percentage increase in serum DIFF concentrations after ECT was 4 times greater (p less than 0.001) in the good outcome group than in the poor outcome group. None of the neurophysin responses to ECT correlated with electroencephalogram-measured seizure duration.
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PMID:Treatment outcome, seizure duration, and the neurophysin response to ECT. 292 Jan 92

The in vitro spontaneous isometric-developed tension (IDT) of uterine horns obtained from diestrous rats exhibited, after 60 min of post-isolation activity, a clear decrease in magnitude, averaging 18.2 +/- 5.2%. In presence of tolbutamide, a concentration-dependent decrease of IDT, significantly greater than the spontaneous reduction (75.1 +/- 5.4%, with tolbutamide at 10(-4) M), was observed. Incubation with propranolol (10(-6) M) or with sotalol (10(-4) M) failed to alter the negative inotropism evoked by tolbutamide. On the other hand, the sulfonylurea (10(-4) M) shifted most points of the dose-response curve to the right for the contractile stimulation elicited by oxytocin, an influence not altered by the simultaneous presence of propranolol or sotalol. Tolbutamide failed to influence the negative inotropic dose-response curve for isoproterenol and did not modify the decrease in contractions evoked by theophylline (10(-4) M). It was also found that tolbutamide was devoid of action on the basal release of prostaglandin E2 from uterine strips and on the positive inotropic dose-response curve for added PGE2 or PGF2 alpha, constructed in presence of indomethacin (5 X 10(-6) M). The present findings do not permit a simple explanation regarding possible factors underlying the negative uterine inotropic influence of tolbutamide in the rat uterus. However, it appears that alterations in the integrity of tissue excitability and contractile apparatus, adrenergic implications, changes in uterine cAMP levels, inhibition of cyclo-oxygenase or low PEG2 synthesis and release, are not plausible mechanisms to explain the negative inotropism of tolbutamide. Therefore, it is suggested that the contractile depression evoked by tolbutamide and its action on the contractile effect of oxytocin might be linked to the impaired synthesis of other prostanoids, namely PGF2 alpha, PGI2 or PGD2, although the participation of not yet determined factor(s), namely changes in Ca2+ ion movements, cannot be discarded.
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PMID:Tolbutamide in vitro diminishes spontaneous and oxytocin-induced contractions of uterine smooth muscle from diestrous rats. 348 42

1. Extracellular recordings in pentobarbitone anaesthetized male Long-Evans rats examined the influence of electrical stimulation in the diagonal band of Broca on the excitability of 113 putative vasopressin-secreting and 22 putative oxytocin-secreting neurosecretory neurones in the hypothalamic supraoptic nucleus. 2. Single pulse or repetitive (5-20 Hz) stimulation in the ventral part of the diagonal band evoked a prominent reduction in the excitability of 83% of vasopressin-secreting neurones with no effect on the remainder. Amongst oxytocin-secreting neurones, 59% were unresponsive, 27% responded with an increase in activity while only 14% revealed an inhibitory pattern similar to vasopressin-secreting neurones. 3. Diagonal band stimulation-evoked inhibitions were reversibly abolished by local pressure applications of bicuculline methiodide (100 microM) to twenty out of twenty vasopressin secreting cells tested, whereas strychnine sulphate (100 microM) was without effect on four out of four cells tested. 4. In five out of five vasopressin-secreting cells tested, bicuculline applications reversibly abolished the reduction in their activity that follows peripheral baro-receptor activation. Failure to alter baroreflex-evoked depressions in firing during similar trials with prazosin hydrochloride (10 microM, six cells tested), timolol maleate (20 microM, six cells tested) or strychnine sulphate (100 microM, three cells tested) indicated the specificity of bicuculline's action. 5. These findings suggest that a GABAergic pathway from the diagonal band of Broca preferentially innervates vasopressin-secreting neurosecretory supraoptic nucleus (s.o.n.) neurones, and support the view that the baroreflex-induced depression in firing of s.o.n. vasopressin-secreting neurones is mediated in large part through this input.
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PMID:A gamma-aminobutyric-acid-mediated baroreceptor input to supraoptic vasopressin neurones in the rat. 362 45


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