Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Suckling stimulus did not induce significant release of prolactin (PRL) in lactating homozygous Brattleboro rats, whereas it did it in heterozygous animals. Daily treatment of homozygous rats with vasopressin partly restored the PRL response to suckling. Findings suggest that vasopressin-neurophysin-glycopeptide precursor missing in homozygous Brattleboro rats may play a role in suckling-induced PRL release.
 ...
PMID:Lack of the suckling-induced prolactin release in homozygous Brattleboro rats: the vasopressin-neurophysin-glycopeptide precursor may play a role in prolactin release. 259 13

Evidence is rapidly accumulating that a number of neuropeptides are involved in the central control of male sexual behavior. This is consistent with their neuroanatomical distribution, i.e., in CNS loci previously implicated in the control of this behavior such as the medial preoptic area, and with recent findings that the peptide content of some of these regions is regulated by testosterone or its metabolites. Most of the work has been done using rats, but relevant human studies have been included whenever such material has been available. At this point there are relatively few studies which directly demonstrate the involvement of peptides in this behavior. Inhibitory and facilitatory actions, however, have been demonstrated following injections of peptides, peptide antisera, or antagonists into the CNS of male rats. Significant new developments include demonstrations that injections of substance P and A-MSH directly into the medial preoptic area can facilitate this behavior, while ventricular injection of an oxytocin antagonist can produce a powerful inhibition. The emerging picture is that GnRH, oxytocin, A-MSH and substance P stimulate, while CRF, beta-endorphin, prolactin, and neuropeptide Y are inhibitory. The inhibitory peptides CRF, beta-endorphin and prolactin are related, as they are released in response to stress. This may be relevant to the low level of sexual motivation in some depressed men. Questions concerning sites of action and mechanisms of action which mediate the behavioral effects which have been demonstrated remain largely unanswered.
 ...
PMID:Neuropeptides and male sexual behavior. 267 29

Recent evidence suggests that oxytocin modulates both ACTH and prolactin secretion. The present study was designed to investigate the possible role of oxytocin in the corticosterone and prolactin response to predictable and unpredictable novelty stress. These responses were examined in lactating females (Day 6 and Day 21 postpartum) which had received stress and oxytocin treatment during pregnancy. The results demonstrated that exposure to the novelty stressors during pregnancy resulted in a significant elevation in corticosterone levels of lactating females on Day 6 postpartum. A similar elevation was also observed on Day 21 postpartum for the unpredictable condition. Oxytocin treatment did not, however, significantly affect the corticosterone response to the psychological stressor. Furthermore, prolactin levels were not significantly affected on either Day 6 or Day 21 postpartum by either novelty stress or oxytocin treatment administered during pregnancy. It was suggested that the sustained elevation in corticosterone levels obtained following unpredictable exposure to the stressor had important implications for the lactation process.
 ...
PMID:Psychological stress and administered oxytocin during pregnancy: effect corticosterone and prolactin response in lactating rats. 271 45

Studies were undertaken to investigate the effects of oxytocin induction on prolactin release in term (Group II) and preterm (Group III) mares and to compare these effects to spontaneously foaling mares (Group I). Since physiological concentrations of prolactin in blood have not been measured in the neonatal foal, experiments were designed to monitor prolactin in the cord artery and jugular blood of the foals from all groups of mares. Although prolactin levels varied in term mares (Group I and II) during the last 11 days of pregnancy, an increase was observed between Day -6 and Day 0 (2.7 and 11.9 ng/ml respectively; P less than 0.1). The average concentration of prolactin over the last 4 days (Days -3 to 0) had increased by 40% when compared to the average concentration on Days -6, -5, and -4. These findings indicate a rising trend which appears to occur concomitantly with changes in concentrations of 2 mammary components tested, sodium and potassium. Prolactin concentrations did not significantly increase in term mares after oxytocin treatment or in spontaneously foaling mares. However, the preterm induced mares had higher prolactin concentrations during the first stage of labor (19.3 +/- 7.2 ng/ml) than prior to treatment with oxytocin (4.7 +/- 2.0 ng/ml; P less than 0.01). Levels of prolactin in all groups significantly declined by 20-min post-placental expulsion. For the first 30 min after birth, prolactin concentrations in foals from oxytocin-induced mares appeared to be 2-fold higher than those from spontaneously foaling mares. Thereafter, prolactin values declined to baseline values by 48 hrs. When comparing cord arterial plasma with cord venous plasma in each group, prolactin concentrations were similar. However, the average prolactin levels in both the cord artery and vein appeared higher (ave: 1.1 ng/ml) in Group II and III than in Group I (less than 0.5 ng/ml). From these results, the authors suggest that 1) prolactin may have a role in regulating mammary secretory products in mares just prior to parturition; 2) oxytocin may increase prolactin secretion in preterm induced mares; 3) oxytocin induction may have a short term effect to increase circulatory prolactin concentrations in neonates in utero regardless whether their dams were treated preterm or term.
 ...
PMID:Plasma prolactin concentrations in mares and their neonates after oxytocin induction of parturition. 273 12

The effect of an intravenous bolus injection of cholecystokinin octapeptide (CCK-8; 0.85 micrograms/kg) on the release of cortisol, prolactin, vasopressin, and oxytocin was studied in sheep (n = 10). Concentrations of these hormones were measured in blood samples taken before (-10, 0 min) and after (5, 10, 20 min) administration of a saline vehicle or vehicle + CCK. Following CCK treatment, levels of cortisol were raised after 10 and 20 min, prolactin and vasopressin concentrations were increased after 5 min, and oxytocin secretion was unaffected.
 ...
PMID:Anterior and posterior pituitary hormone release induced in sheep by cholecystokinin. 273 59

The effect of stress during labour on the plasma concentration of prolactin and cortisol was studied in 30 healthy multiparous women. The plasma concentrations of prolactin and cortisol were measured by radioimmunoassay during oxytocin induced labour, spontaneous labour, delivery and postpartum 24 h. The parturients were divided into three groups. The first group was given oxytocin for the induction of labour, the second group was also given oxytocin for the induction of labour and 100 mg of meperidine was administered intramuscularly for relief of pain and anxiety, and the third group was the control group with normal parturients who did not receive any medication. The prolactin levels showed a fall during labour in all the groups, but this fall was more marked in the first group where stress was evident. The concentrations of cortisol tended to increase during labour and reached a maximum at delivery in all three groups but in the meperidine group this level was significantly lower than the first and control groups. These results give further support to the hypothesis that maternal stress leads to a reduced concentration of prolactin and increased concentration of cortisol whereas relief of pain and maternal anxiety with meperidine lessens both effects.
 ...
PMID:Prolactin and cortisol levels during spontaneous and oxytocin induced labour and the effect of meperidine. 278 50

Pharmacological influences on male rat sexual behavior are reviewed in an attempt to identify neurotransmitters and their respective receptor types that regulate various factors comprising the behavioral pattern. Evidence is presented that: (1) serotonergic influence is generally inhibitory to sexual behavior, although two receptor subtypes may lower ejaculation threshold; (2) dopaminergic agonists facilitate several aspects of copulatory behavior and ex copula genital responses; (3) noradrenergic activity appears to increase sexual arousal; (4) cholinergic agonists facilitate ejaculation, or in some cases, delay or prevent initiation of copulation; (5) GABA agonists inhibit sexual responses both in and ex copula; (6) opiate agonists appear to inhibit copulation and penile reflexes, although antagonists have mixed effects; (7) ACTH and MSH peptides promote copulatory behavior and genital responses; (8) oxytocin facilitates ex copula penile responses, but may contribute to postejaculatory refractoriness; and (9) long-term exposure to prolactin inhibits sexual behavior and penile responses. Although some progress has been made in identifying neurotransmitter-receptor effects on behavioral components, copulatory behavior is complex and no drug has been found to affect only a single component. Furthermore, drug specificity is only relative.
 ...
PMID:Pharmacological analysis of male rat sexual behavior. 283 May 64

The responses of plasma adrenocorticotrophin (ACTH), cortisol, growth hormone (GH) and prolactin to insulin-induced hypoglycaemia were studied in six lean male subjects (age 22-29 years). Intravenous insulin tests were performed with and without oxytocin infusion. Blood sugar nadir occurred at the onset of symptoms (time S) with no significant differences between oxytocin and saline infusion. During the oxytocin infusion mean plasma oxytocin increased from 1.9 pmol/l to 138 pmol/l. Peak increase in plasma ACTH (oxytocin 266 +/- 54 ng/l; saline 281 +/- 43 ng/l, mean +/- SEM) was at S + 10 min while peak plasma cortisol (oxytocin 680 +/- 47 nmol/l: saline 656 +/- 40 nmol/l) was measured at S +/- 60 min, peak GH (oxytocin 96 +/- 17.8 mU/l; saline 106 +/- 18.6 mU/l) at S + 60 min and prolactin (oxytocin 1332 +/- 239 mU/l; saline 1242 +/- 273 mU/l) at S + 30 min. There were no significant differences in plasma concentrations of ACTH, cortisol, GH or prolactin between saline and oxytocin infusion. The results indicate that oxytocin has no effect on plasma ACTH, cortisol, GH and prolactin responses to insulin-induced hypoglycaemia. In particular they fail to support previous studies which suggested an inhibitory role for oxytocin in ACTH secretion.
 ...
PMID:The effect of oxytocin infusion on adenohypophysial and adrenal cortical responses to insulin-induced hypoglycaemia. 285 20

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.
 ...
PMID:Oestrogen-stimulated neurophysin and outcome after electroconvulsive therapy. 287 18

Melanin concentrating hormone (MCH) is a heptadecapeptide isolated from chum salmon (Oncorhynchus keta) pituitaries. The peptide has been isolated from whole brain extract at a low yield of 1.2 micrograms/1300 brains. MCH activity in the hypothalamus was characterised by in vitro scale bioassay and radioimmunoassay. Specificity of these assay systems was examined with neurotransmitters such as epinephrine, norepinephrine, and dopamine, hypothalamic hormones such as somatostatin, isotocin, Arg-vasotocin, oxytocin, and Arg-vasopressin, and salmon prolactin and its chymotryptic peptide or salmon PRL176-187. Among them only salmon PRL176-187 exhibited weak activities in both assays. The neurotransmitters were 10(4) to 10(5) times less potent than MCH in the bioassay. MCH concentrations in a pituitary and a hypothalamus were estimated as 5300 +/- 750 ng (ca. 106 micrograms/g) and 48 +/- 9.5 ng (ca. 1.6 micrograms/g), respectively, by radioimmunoassay. Lysyl endopeptidase digestion of the hypothalamic extract resulted in a significant increase of biological activity as well as of immunoreactivity. Gel filtration of the hypothalamic extract and subsequent enzymatic digestion revealed that the fractions at higher molecular weight were contributory to the increase in the activities.
 ...
PMID:Characterization of melanin concentrating hormone in teleost hypothalamus. 288 42


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>