Some effects of inhibiting endogenous prostaglandin formation on the responses of the cat spleen

Abstract

Summary Cat isolated spleens release prostaglandins into the venous effluent in response to stimuli such as nerve stimulation, noradrenaline and angiotensin II. The release of prostaglandins is abolished by pre‐treatment of the spleen with indomethacin (0·3–5 μg/ml). The capsular and vascular responses to the different stimuli are augmented after inhibition of prostaglandin release. The prevention of prostaglandin release, as well as the augmentation of vascular and capsular responses, are reversible after indomethacin treatment is stopped. The role of prostaglandins as modulators of the responses to several stimuli is discussed.

The contribution of prostaglandin production to contractions of the isolated uterus of the rat

“…The prostaglandins so produced would then potentiate the contraction induced by oxytocin, perhaps by increasing the rate and spread of depolarization as suggested by Aiken & Vane, 1971;1973;Ferreira, Moncada & Vane, 1973). If the capacity of the uterus to synthesize prostaglandins increases towards the end of pregnancy (see below) this would help to explain the progressive increase in sensitivity of the pregnant human uterus to oxytocin (Caldeyro-Barcia & Sereno, 1961;Brummer, 1971).…”

Prostaglandin Release From Cat and Dog Spleen

“…Ferreira et al (1973) using the saline-perfused cat spleen detected no basal or stimulated release of prostaglandin during the first hour of perfusion. Thereafter, a basal release of up to 4 ng/ml (prostaglandin E2 equivalents) was found.…”

“…2 Piesent address: Department of Oral Medicine, Dental School, University of Edinburgh. (Hedqvist, 1970a) but there is evidence that the spleens of these two species are not comparable in their ability to release prostaglandins in response to nerve stimulation (Ferreira, Moncada & Vane, 1973;Peskar & Hertting, 1973;Hoszowska & Panczenko, 1974;cf. Davies, Horton & Withrington, 1968;Gilmore, Vane & Wyllie, 1968;Ferreira, Moncada & Vane, 1971).…”

Prostaglandins and the mechanism of analgesia produced by aspirin‐like drugs

“…However, phenoxybenzamine abolished the release by adrenaline but not that by bradykinin. We have not attempted to characterize further the prostaglandin(s) released, but in other dog and cat spleen perfusions the release was predominantly of prostaglandin E2 (Davies, Horton & Withrington, 1968;Gilmore et al, 1968;Ferreira, Moncada & Vane, 1973). Bradykinin also causes release of prostaglandin E2 from dog kidney (McGiff, Terragno, Malik & Lonigro, 1972).…”