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)

The acute in vitro action of adrenocorticotropin (ACTH) and corticosterone alone and in combination were determined in the Cloudman S-91 melanoma grown in vivo. Hormone-treated melanoma dice (5-240 min) were analyzed for tyrosinase activity (EC 1.14.18.1), cyclic AMP (cAMP) and cyclic GMP (cGMP). ACTH elevated cAMP levels in the S-91 melanoma. However, these increases in cAMP were not accompanied by increased tyrosinase activity. Corticosterone depressed cAMP levels while stimulating tyrosinase activity. ACTH plus corticosterone produced an early cAMP peak followed by depression. ACTH plus corticosterone stimulated tyrosine activity coincident with the early cAMP peak followed by a drop in tyrosinase activity which was subsequently elevated. cGMP levels were not altered by any hormone treatment. The results indicate that cAMP is not the sole modulator of tyrosinase activity and suggest the interaction of ACTH, corticosterone and cAMP in the regulation of melanoma tyrosinase activity.
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PMID:Glucocorticoid modulation of adrenocorticotropin-induced melanogenesis in the Cloudman S-91 melanoma in vitro. 20 85

The acute in vitro action of adrenocorticotropin (ACTH) and corticosterone alone and in combination were determined in the Harding-Passey (HP) melanoma grown in vivo. Hormone treated melanoma dice (5--240 min) were analyzed for tyrosinase activity, cyclic AMP (cAMP) and cyclic GMP (cGMP). ACTH elevated cAMP and cGMP levels 20- and 13-fold, respectively, in the HP melanoma. However, these large increases in cyclic nucleotide levels were accompanied by only a 49% increase in tyrosinase activity. Corticosterone elicited a similar response. ACTH plus corticosterone produced an early cAMP and cGMP peak followed by depression. ACTH plus corticosterone stimulated tyrosinase activity coincident with the early cyclic nucleotide peak followed by a drop in tyrosinase activity which was subsequently elevated. The results indicate that neither cAMP nor cGMP are the sole modulators of tyrosinase activity and suggest the interaction of ACTH, corticosterone and cyclic nucleotides in the regulation of melanoma tyrosinase activity.
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PMID:Interaction of ACTH, corticosterone and cyclic nucleotides in Harding-Passey melanoma melanogenesis. 21 Jul 23

The acute in vitro action of ACTH and corticosterone individually and in combination were determined in the B-16 melanoma grown in vivo. ACTH elevated levels 10-fold while tyrosinase activity generally was depressed. Corticosterone depressed cAMP levels and tyrosinase activity. ACTH in the presence of corticosterone produced a coincident peak in tyrosinase activity and cAMP levels followed by a depression of enzymatic activity. The results demonstrate that cAMP is not the sole modulator of tyrosinase activity and that ACTH, corticosterone and cAMP interact in the regulation of B-16 melanoma tyrosinase activity.
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PMID:Effect of ACTH and corticosterone on melanogenesis and cyclic nucleotide levels in the B-16 melanoma. 22 4

Female rats rendered "pseudopregnant" by treatment with PMS and hCG and ovariectomized rats injected with estradiol and progesterone (OVX-E2-P) were subjected to cortical spreading depression (SD). Within 7-10 min under ether anesthesia in a stereotaxic instrument a frontal craniotomy was performed and a cotton ball saturated with physiological saline (control) or 25% KCl was applied to the exposed dura, covered with dental cement and skin sutured. The animals were then placed in separate containers in an isolated room and decapitated for collection of trunk blood at 0, 15, 30, or 60 min after surgery. In PMS-hCH saline-treated control animals, prolactin levels had dropped by 15 and 30 min when compared with the zero-time values but by 60 min had increased significantly above the 30-min level. At that time (60 min), prolactin values in the KCl group were significantly lower than in the controls. Corticosterone levels were high at both 15 and 60 min in control and KCl groups. In OVX-E2-P control animals, plasma prolactin levels also rose at 60 min compared with 15- and 30-min samples and at 60 min were significantly higher than in the KCl group. In control animals, LH levels were lower at 15 and 60 min than at zero time, but they remained unchanged in the KCl group. The dato are interpreted as indicating that cortical SD suppresses the stress responses observed in saline-treated control animals.
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PMID:Effects of spreading depression on stress-induced changes in plasma prolactin and LH. 118 96

A hind-leg subcutaneous saline injection into rats at night elicits a decrease in N-acetyltransferase (NAT) activity and melatonin content of the pineal gland. The decrement in pineal melatonin production after saline injection is prevented by adrenalectomy. The present studies were undertaken to determine what factor(s) from the adrenal gland cause(s) the drop in pineal melatonin production after saline injection at night. In the first study, groups of intact and adrenal-demedullated male rats were given a saline injection at 23.10 h (3 h, 10 min after lights off) and their pineals were collected 15 or 30 min later. Pineal NAT activity was depressed in both intact and adrenal-demedullated rats at 15 min postinjection as compared to their respective control animals. Pineal melatonin levels exhibited a drop in intact animals at 15 min and in adrenal-demedullated rats at 30 min. In a second study, hypophysectomy was found to prevent the drop in nocturnal pineal NAT activity and melatonin levels normally associated with a hind leg injection of saline. Finally, in a third experiment, groups of hypophysectomized rats were injected i.p. with corticosterone at 23.10 h and killed 10, 25 or 40 min postinjection. Corticosterone injection in hypophysectomized rats produced a response similar to that caused by saline injection in intact animals: NAT activity was depressed at 10 min and melatonin content was lowered at 25 min. These results suggest that the adrenal-mediated depression in melatonin synthesis after saline injection at night in rats may be elicited by an adrenal cortical hormone (corticosterone) and apparently does not involve the release of factors from the adrenal medulla.
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PMID:The depression in rat pineal melatonin production after saline injection at night may be elicited by corticosterone. 340 9

Spleen cells from mice immune to Plasmodium berghei exhibited a significantly increased in vitro proliferative response to parasitized reticulocytes compared to spleen cells from normal mice. The specific response to malaria antigen was decreased in spleen cells from pregnant immune mice in contrast to the nonspecific response to the mitogen phytohemagglutinin. Addition of mouse serum to spleen cell cultures of immune mice depressed both the phytohemagglutinin and the specific proliferative response, whereas serum of pregnant mice exerted an even stronger inhibition than serum of nonpregnant mice. Charcoal adsorption of mouse sera for the elimination of steroid hormones removed the serum dependent immunosuppression from normal as well as pregnant serum. Corticosterone added to the spleen cell cultures depressed also the proliferative response. These findings demonstrate that the response to malaria antigen is decreased in immune mice during pregnancy. The possible effect of serum corticosterone on the depression of the immune response is discussed.
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PMID:Plasmodium berghei: reduction of the mouse's specific lymphoproliferative response in relation to corticosterone and pregnancy. 352 63

1. Corticosterone (680 micrograms/kg body weight per day) given as six daily injections to 3- or 7-week-old chicks decreased weight gain, but increased food consumption, abdominal fat pad weight, skin dry matter, relative liver size and liver fat concentration. 2. Time of day of injection did not modify the response to corticosterone of 3-week-old chicks kept under natural daylight nor of 7-week-old broilers receiving additional illumination. 3. Pure White Rock chicks and Cornish X White Rock crossbred chicks responded similarly to corticosterone at 3 weeks of age. 4. Seven-week-old female birds treated with corticosterone had significantly larger abdominal fat pads than similarly treated males. 5. Corticosterone injection was more effective in increasing the proportion of liver fat in 7-week-old birds than in 3-week-old chicks. 6. The increased amount of abdominal and liver fat due to corticosterone injections administered at 3 weeks of age disappeared after 3 weeks, but growth depression was still evident.
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PMID:Corticosterone and fat deposition in broiler chicks: effect of injection time, breed, sex and age. 707 85

Hippocampal structures are a major target for adrenal steroid hormones, and hence these neural regions are some of the most likely mediators of the effects of adrenocortical steroids on behavior. Memory disturbance, in particular biasing toward negative contents, are part of the symptomatology presented by depressive patients. In turn, a sizeable subset of depression also presents with hypercortisolemia. Adrenocortical hormones are also known to affect memory processes. Hippocampal formation is essential for declarative memory. We thought it appropriate then to study the effects of adrenal steroids on long-term potentiation, a putative memory mechanism in the hippocampus. Two clearly distinguished components of the evoked response to perforant path stimulation can be studied in the hippocampus: the excitatory postsynaptic potential (EPSP) which denotes the graded depolarization of the somatodendritic region of the neuron and the population spike (PS), a manifestation of the all-or-none-discharge of the cell action potential. Corticosterone had a significant depressant effect on the EPSP component of the evoked response immediately and 15 min after injection. Thereafter EPSP amplitudes were within normal values. Corticosterone significantly decreased the PS immediately after the train, the component remaining low 30 min after the train. 5 alpha-Dihydrocorticosterone (a ring A-reduced metabolite of corticosterone) significantly reduced the PS component of the response at all times after injection. 18-Hydroxydeoxycorticosterone and deoxycorticosterone significantly decreased both EPSP and PS components of the evoked response from the time of infusion. Contrary to expectation, tetrahydrodeoxycorticosterone was ineffective in decreasing and if anything, enhanced the development of long-term potentiation. 18-Hydroxydeoxycorticosterone 21-acetate behaved like vehicle, except for the first 30 min after injection when the EPSP was decreased. Allotetrahydroprogesterone decreased all EPSP's values and had no effect in the PS development in comparison with vehicle. The suggestion is made that the study of steroidal effects on hippocampal LTP can serve as a preclinical model of some aspects of depression in a specific subset of the disease.
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PMID:Effects of adrenocortical steroids on long-term potentiation in the limbic system: basic mechanisms and behavioral consequences. 825 10

To investigate the role of the hypothalamic-pituitary-adrenal (HPA) axis in behavioral responses to infection, we studied the effects of corticosterone on depressed social behavior induced by peripheral and central interleukin-1 beta (IL-1 beta) in the rat. Intact and adrenalectomized (ADX) rats were injected i.p. with IL-1 beta (500 ng) and their motivation to investigate a juvenile conspecific was assessed. Whereas ADX rats showed a marked depression in social behavior following i.p. IL-1 beta, intact controls did not. To verify that corticosterone was responsible for inhibiting the effects of IL-1 beta, corticosterone pellets or placebos were implanted i.p. in ADX rats. Following i.p. injection of IL-1 beta, ADX rats with placebos experienced depressed social behavior. Corticosterone replacement, however, reversed this effect in ADX rats, confirming that corticosterone modulates the behavioral effects of peripheral IL-1 beta. To determine if corticosterone modulates sickness behavior directly in the CNS, intact and ADX rats were injected i.c.v. with IL-1 beta or lipopolysaccharide (LPS). Although centrally administered IL-1 beta depressed social behavior to a similar extent in intact and ADX rats, the depression was prolonged in ADX rats. However, social behavior of ADX rats injected i.c.v. with LPS was depressed more than in intact controls, and this effect was reversible by corticosterone replacement. These results are interpreted to indicate that corticosterone inhibits the behavioral effects of IL-1 beta in the periphery and, perhaps, in the CNS. That the behavioral effects of central LPS were inhibited by corticosterone suggests the HPA axis may modulate behavior by regulating cytokine synthesis in the CNS.
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PMID:Role of corticosterone in the behavioral effects of central interleukin-1 beta. 897 27

Arginine metabolism plays an important role in many aspects of inflammation and wound healing. In this study, we tested the hypothesis that steroids and vitamin A have differential effects on arginine metabolism and thereby may provide a mechanism by which steroids impair wound healing, and vitamin A improves this impairment. Rats were treated with subcutaneous corticosterone pellets 2 days prior to wounding. Intraperitoneal injections of all-trans retinoic acid in peanut oil were administered at the same time and repeated 2 and 4 days later. Polyvinyl alcohol sponges were implanted subcutaneously through a dorsal incision. On Postwounding Days 1, 5, 10, and 15, wound fluid was recovered from the sponges and assayed for nitrite/nitrate (NOx), citrulline, arginine, and ornithine concentrations as well as arginase activity. Steroid treatment decreased the metabolism of arginine to nitric oxide in the early phase of wound healing, and retinoic acid did not change this relationship. Corticosterone also decreased metabolism of arginine to ornithine in the later wound. This depression was inhibited by concomitant administration of retinoic acid. Considering the importance of nitric oxide in host defense and ornithine as a precursor for polyamine and proline synthesis, these data provide a mechanism by which vitamin A improves wound strength, but does not improve wound infection rates in steroid-treated animals.
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PMID:Altered wound arginine metabolism by corticosterone and retinoic acid. 922 33


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