Effect of cyclooxygenase inhibitors on the vasopressin induced ACTH and corticosterone response during crowding stress

• Autorzy: Bugajski J. , Gadek-Michalska A.
• Języki publikacji: EN

Abstrakty

EN

The aim of the present study was to compare the effect of social stress on the corticotropin releasing hormone (CRH) and arginine vasopressin (AVP)-induced pituitary-adrenocortical activity. Also the significance of prostaglandins (PG) generated by constitutive and inducible cyclooxygenase (COX-1 and COX-2) in the stimulation of hypothalamic-pituitary-adrenal (HPA) axis by AVP under basal and crowding stress conditions was investigated. The control rats were housed 7 in a standard cage and stressed rats were crowded 24 in a cage of the same size during 7 days. The activity of HPA axis was determined by measuring plasma ACTH and serum corticosterone levels 1 h after i.p. AVP administration. Indomethacin (2.0 mg/kg i.p.), a non-selective COX inhibitor, piroxicam (0.2, 2.0, and 5.0 mg/kg), a more potent COX-1 than COX-2 inhibitor, and compound NS-398 (0.2 and 2.0 mg/kg) a selective COX-2 inhibitor, were administered i.p. 15 min prior to AVP (5.0 µg/kg i.p.) to control or crowded rats. The obtained results indicate that social stress for 7 days considerably inhibits the stimulatory action of AVP on ACTH secretion, while it intensifies the CRH-induced ACTH secretion. Indomethacin, piroxicam and NS-398 significantly diminished the AVP-elicited ACTH and corticosterone secretion in non-stressed rats. None of these COX antagonist induced any significant inhibition of the AVP-induced ACTH and corticosterone secretion in stressed rats. Therefore, PG generated by COX-1 or COX-2 do not participate to a significant extent in the HPA stimulation by AVP during crowding stress. These results suggest that social crowding stress desensitizes the PG stimulatory mechanism which considerably mediates the AVP-induced HPA stimulation under basal conditions. The results contrast with a lack of any involvement of PG in the CRH-induced stimulation of HPA response under basal or crowding stress conditions.

Słowa kluczowe

EN

prostaglandin; pituitary-adrenocortical activity; vasopressin; corticosterone; cyclooxygenase-2; cyclooxygenase-1; cyclooxygenase; social stress; corticotrophin releasing hormone; crowding stress; hypothalamic-pituitary-adrenal axis

• Wydawca: -
• Czasopismo: Journal of Physiology and Pharmacology
• Rocznik: 2003
• Tom: 54
• Numer: 2
• Opis fizyczny: p.247-256,fig.

Twórcy

autor

Bugajski J.

• Polish Academy of Sciences, 12 Smetna Street, 31-343 Krakow, Poland

autor

Gadek-Michalska A.