Animals ; Cells, Cultured ; Cyclic AMP ; metabolism ; Pituitary Gland, Anterior ; cytology ; drug effects ; metabolism ; Rats ; Substance P ; pharmacology

OBJECTIVETo study the effects of C. versicolor petroleum ether extracts (CVPE) on the adenohypophysis androgen receptor level in mature castrated male rats.

METHODAll the rats in experiment were anesthetized for bilateral testicular and epididymis removal under sterile condition. The rats were randomized into four groups on the 14 th day after operation. The first group was intragastric physiological saline for castratered control group. The second group was intragastric CVPE 2 g x kg(-1) for low-dose group. The third group was high-dose group by giving CVPE 4 g x kg(-1). The fourth group was injected hypodermic testosterone propionate for positive-effect drug treatment group. The drug was given orally to animals one time a day successively for 21 days. The androgen receptor (AR) in adenohypophysis of mature castrated male rats was determined by the immunohistochemistry method and the level of serum testosterone (T) were determined by the radio-immunoassay after ig CVPE for 21 days.

RESULTThe immunohistochemistry results showed that positive cell numbers of androgen receptor in positive control and each CVPE groups were more than those in the castrated control group. The serum T level was increased greatly in mature castrated male rats treated with CVPE compared with the control group (P < 0.05, P < 0.01).

CONCLUSIONThe results show that CVPE can increase the adenohypophysis androgen receptor and serum T level in mature castrated male rats. It is indicated that CVPE has the effects on the hypophysis function.

Animals ; Lizards ; Male ; Materia Medica ; isolation & purification ; pharmacology ; Orchiectomy ; Pituitary Gland, Anterior ; drug effects ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Receptors, Androgen ; metabolism ; Testosterone ; blood

OBJECTIVETo study the effects of cadmium chloride in anterior pituitary and the relation between apoptosis and expression of procaspase-9 mRNA.

METHODSIn vivo studies:40 SD male rats were randomly distributed into four groups which were administered with CdCl2 at different doses by gavage for 6 weeks;

IN VITRO STUDIESthe rats' anterior pituitary cells were primarily cultured for 120 hours, then treated with CdCl2 at the dose of 0, 1.56, 3.12, 6.25, 12.50, 25.00, 50.00, 100.00 micromol/L for 6 hours; The indices included: expression of procaspase-9 mRNA, detection of apoptosis with TUNEL assay.

RESULTSThe results showed the excretion of ACTH, LH seemed to be decreased dramatically and the apoptosis inclined to enhance remarkably, and further more, the expression of procaspase-9 mRNA appeared to be increased significantly as compared with those of the control. It was show that a dose-effect relationship between the CdCl2 dosing and indices above with the regression analysis and a linear correlation between the mean gray value of apoptosis cell and the relative gray value of procaspase-9 mRNA positive cell. The results indicated that damnification, for example, apoptosis could be caused by certain dose of CdCl2 in anterior pituitary cells with dose dependent manner. Caspase-9 might play a role in the occurrence of apoptosis.

CONCLUSIONIt was suggested that cadmium could induce apoptosis of anterior pituitary both in vivo and in vitro in the manner of dose-dependent, and caspase-9 might play a role during above processes.

Animals ; Apoptosis ; drug effects ; Cadmium Chloride ; administration & dosage ; toxicity ; Caspase 9 ; genetics ; Cells, Cultured ; Dose-Response Relationship, Drug ; Male ; Pituitary Gland, Anterior ; cytology ; drug effects ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; Signal Transduction ; drug effects

According to our previous studies together with others, GnRH, a hypothalamic decapeptide, has been known to be a major regulator for LH release and its subunit biosynthesis in anterior pituitary gonadotropes. But the precise mechanisms by which GnRH exerts stimulatory effects on LH release and its subunit biosynthesis have not been clearly understood. In the present study we examined the effect of GnRH on protein kinase C (PKC) activity and intracellular cAMP content in cultured anterior pituitary cells of rat to clarify whether PKC or cAMP are involved in GnRH action. Moreover, we examined the effects of staurosporine (ST), a PKC inhibitor and 2',3'-dideoxyadenosine (2',3'-DDA), an adenylate cyclase inhibitor, on LH release and steady state LH beta subunit mRNA levels in cultured anterior pituitary cells of rat. PKC activity was rapidly increased within 30 min after GnRH treatment whereas intracellular cAMP level was elevated 18 h after GnRH treatment. ST significantly inhibited GnRH-induced LH release and LH beta subunit mRNA levels in a dose-dependent manner, showing an half maximal response at 50 nM ST. 2',3'-DDA inhibited GnRH-induced LH release and LH beta subunit mRNA levels in a dose-dependent manner in pituitary cells. From these results, it is suggested that GnRH stimulates LH beta subunit mRNA level as well as LH release in anterior pituitary cells and this GnRH action might be mediated by PKC activation and cAMP stimulation.
Adenylate Cyclase/*antagonists & inhibitors ; Alkaloids/*pharmacology ; Animal ; Cells, Cultured ; Cyclic AMP/metabolism ; Dideoxyadenosine/*pharmacology ; Female ; Gonadorelin/*pharmacology ; Luteinizing Hormone/*biosynthesis/*metabolism ; Pituitary Gland, Anterior/*drug effects/metabolism ; Protein Kinase C/*antagonists & inhibitors/metabolism ; Rats ; Rats, Sprague-Dawley ; Staurosporine ; Support, Non-U.S. Gov't