IN-VIVO ASSAY FOR HYPOTHALAMIC PROLACTIN-INHIBITING FACTOR

1970 ◽  
Vol 46 (2) ◽  
pp. 237-241 ◽  
Author(s):  
A. DANON ◽  
S. DIKSTEIN ◽  
F. G. SULMAN
Keyword(s):  
Cerebral Cortex ◽  
Adult Male ◽  
Male Rats ◽  
Assay Method ◽  
Rat Hypothalamus ◽  
Inhibiting Factor ◽  
Prolactin Content ◽  
Pituitary Prolactin ◽  
Dose Dependent

SUMMARY Treatment of intact adult male rats with 10 mg. perphenazine (Trilafon)/kg. resulted in a decrease in the prolactin content of the pituitary within 1 hr. This decrease was probably due to suppression of the hypothalamic prolactin-inhibiting factor (PIF). Subsequent intracarotid infusion of neutralized acid extracts of rat hypothalamus restored the pituitary prolactin content. This effect was dose-dependent within a range of ½-2 hypothalami. Infusion of extracts of cerebral cortex failed to increase pituitary prolactin. The response to the hypothalamic extracts is considered to be specific for PIF and is proposed as an assay method for PIF.

Increased dopaminergic inhibition of prolactin in the hypoprolactinaemic IPL nude rat

1985 ◽  
Vol 107 (3) ◽  
pp. 325-329 ◽  
Author(s):  
H. Cohen ◽  
I. Sabbagh ◽  
P. Guillaumot ◽  
J. Bertrand
Keyword(s):  
Adult Male ◽  
Physiological Saline ◽  
Prolactin Secretion ◽  
Male Rats ◽  
Saline Control ◽  
Plasma Prolactin ◽  
Synthesis Inhibitor ◽  
Nude Rat ◽  
Prolactin Content ◽  
Pituitary Prolactin

ABSTRACT In this study, aimed at investigating whether dopaminergic regulation of prolactin could be implicated in the hypoprolactinaemia observed in the IPL nude rat, dopaminergic inhibition of prolactin was suppressed using a catecholamine synthesis inhibitor α-methyltyrosine (MT) and a dopaminergic antagonist sulpiride. Adult male rats (IPL nude and normal) were injected through implanted atrial cannulae with either MT (250 mg/kg) or physiological saline (control). Rats were decapitated 2 h after the injection. Plasma prolactin levels, compared with basal values, increased by 15·6 ± 1·9 (s.e.m.)- and 5·89 ± 0·6-fold in IPL nude and normal rats respectively. This difference was highly significant. The pituitary prolactin content was decreased in both groups. In a second experiment, adult male IPL nude or normal rats were injected with either sulpiride (1 mg/kg) or saline and decapitated 2, 4, 8, 12, 14 and 24 h later. Plasma prolactin levels, compared with basal values, were increased in rats injected with sulpiride by 9·2 ± 1·8 and 3·4 ± 0·7-fold in IPL nude and normal rats respectively. The pituitary prolactin content was reduced more in IPL nude than in normal sulpiride-injected rats. These data suggest that prolactin secretion, as well as synthesis, is under an increased dopaminergic inhibition in the male IPL nude rat. J. Endocr. (1985) 107, 325–329

THE AMYGDALA AND THE CONTROL OF GONADOTROPHIN SECRETION

1972 ◽  
Vol 70 (2) ◽  
pp. 209-219 ◽  
Author(s):  
O. Schiaffinin ◽  
L. Martini
Keyword(s):  
Cerebral Cortex ◽  
Oxygen Consumption ◽  
Metabolic Activity ◽  
Adult Male ◽  
Male Rats ◽  
Gonadotrophin Secretion

ABSTRACT In adult male rats, the oxygen consumption of the amygdala is increased following castration and decreased following hypophysectomy. When both operations are performed in the same animal, the metabolic activity of the amygdala is as low as that found following hypophysectomy only. The stimulating effect of castration on amygdalar oxygen consumption can be reversed by administering in vivo, to castrated animals, adequate amounts of testosterone, though testosterone is completely ineffective if added in vitro to the incubation media containing amygdalar tissue taken from castrated animals. In vivo treatment of castrated hypophysectomized animals with LH and FSH increases the metabolic activity of the amygdala; moreover, the in vitro addition of FSH or of LH to amygdalar slices taken from normal animals is capable of increasing the oxygen consumption of this structure to levels similar to those found in the amygdala of castrated animals. None of the experimental manipulations used proved capable of modifying the oxygen consumption of the hippocampus or of the cerebral cortex.

Role of Quercetin on PCBs (Aroclor-1254) Induced Impairment of Dopaminergic Receptor mRNA Expression in Cerebral Cortex of Adult Male Rats

2011 ◽  
Vol 36 (8) ◽  
pp. 1344-1352 ◽  
Author(s):  
Rasiah Pratheepa Kumari ◽  
Kandaswamy Selvakumar ◽  
Senthamilselvan Bavithra ◽  
Rafiq Zumaana ◽  
Gunasekaran Krishnamoorthy ◽  
...  
Keyword(s):  
Cerebral Cortex ◽  
Mrna Expression ◽  
Adult Male ◽  
Male Rats ◽  
Aroclor 1254 ◽  
Dopaminergic Receptor ◽  
Receptor Mrna

In vivo metabolism of 3H-testosterone in adult male rats: Effects of estrogen administration

Steroids ◽  
1975 ◽  
Vol 26 (1) ◽  
pp. 137-147 ◽  
Author(s):  
D.K.H. Lee ◽  
C.E. Bird ◽  
A.F. Clark
Keyword(s):  
Adult Male ◽  
Male Rats ◽  
In Vivo Metabolism ◽  
Estrogen Administration

PROLACTIN STIMULATION TEST WITH PERPHENAZINE: AN EVALUATION OF PLASMA PROLACTIN LEVELS AND PITUITARY SECRETORY ACTIVITY IN THE RAT

1976 ◽  
Vol 68 (3) ◽  
pp. 355-368 ◽  
Author(s):  
A. A. VAN DER GUGTEN ◽  
P. C. SAHULEKA ◽  
G. H. VAN GALEN ◽  
H. G. KWA
Keyword(s):  
Adult Male ◽  
Secretory Activity ◽  
Female Rats ◽  
Male Rats ◽  
Plasma Prolactin ◽  
Prolactin Release ◽  
Oestrogen Treatment ◽  
Endocrine Status ◽  
Pituitary Prolactin ◽  
Single Plasma

SUMMARY Many investigations of the regulation of prolactin synthesis and release are based on single plasma prolactin determinations. The purpose of the present experiment was to ascertain whether groups of rats (i.e. young or adult, male or female animals, being either intact, gonadectomized or gonadectomized and treated with oestrone), differing in age and/or endocrine status, will react to a single dose of perphenazine by an acute release of pituitary prolactin in proportion to their initial plasma prolactin levels. No consistent relation existed between the classification of the twelve groups of rats into three categories of basal plasma prolactin levels (i.e. < 20, 25–50, > 125 ng/ml) and their response to perphenazine. Even though all groups showed a highly significant increase of plasma prolactin levels the magnitude of the maximum prolactin response at 30 min varied greatly within the groups of one category and thus was not related to the initial prolactin levels. The effect of 14 days of oestrone treatment in increasing plasma prolactin levels in gonadectomized animals was greatest in young and adult male rats, less in young females and not significant in adult females. The results obtained after perphenazine treatment in the latter group made it clear that the effect of oestrogen treatment on prolactin release can be completely blocked by increasing synthesis and/or release of the prolactin-release inhibiting factor (PIF). Since perphenazine induces decrease of pituitary prolactin and a concomitant increase of plasma prolactin levels through lowered PIF-action, the positive effect of oestrogens on prolactin release (as observed in gonadectomized male and young female rats) apparently is caused by a different mode of action. The implications of these findings for the regulation of prolactin release, as affected by the endocrine status of the rat, is discussed. Moreover, comparison of prolactin lost from the pituitary and gained in the circulation of the experimental animals, with amounts of prolactin that were observed to disappear from plasma during the experiment, provided suggestive evidence that the capacity to synthesize and/or eliminate prolactin, after a sudden provoked release of the hormone, differed among the groups. The rates of synthesis by the pituitary, of release from the pituitary into the circulation as well as of elimination of the hormone from the circulation (equally involved in determining actual plasma levels) are thought, therefore, to be far more important for the elucidation of prolactin regulation than single plasma prolactin determinations.

Effect of Melatonin on Glutamate: BDNF Signaling in the Cerebral Cortex of Polychlorinated Biphenyls (PCBs)—Exposed Adult Male Rats

2015 ◽  
Vol 40 (9) ◽  
pp. 1858-1869 ◽  
Author(s):  
S. Bavithra ◽  
E. Sugantha Priya ◽  
K. Selvakumar ◽  
G. Krishnamoorthy ◽  
J. Arunakaran
Keyword(s):  
Cerebral Cortex ◽  
Polychlorinated Biphenyls ◽  
Adult Male ◽  
Male Rats ◽  
Bdnf Signaling
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