THE OCCURRENCE OF PROSTAGLANDIN E₂ IN SPLENIC VENOUS BLOOD OF THE DOG FOLLOWING SPLENIC NERVE STIMULATION

Abstract

Prostaglandins are released when the sympathetic nerves supplying the rat epididymal fat pad in vitro are stimulated (Shaw, 1966). It is not yet known whether this is a general phenomenon associated with adrenergic nerve stimulation but the experiments described in this paper show that prostaglandin E2 is released when the splenic nerve is stimulated. A preliminary account of this work has already been published (Davies, Horton & Withrington, 1967).In the investigation reported here we collected venous blood samples from the perfused dog's spleen in order to detect any prostaglandin release when the splenic nerve was stimulated. A large increase in prostaglandin E2 output was found. METHODSBlood-perfused dog spleen. An isolated spleen was perfused with blood from the femoral artery of a second (donor) dog using the technique described in the following paper (Davies & Withrington, 1968). The splenic venous blood was returned to the femoral vein of the donor except during the collection of a sample, when it was diverted out of a side arm. During the collection of a sample, blood from a reservoir was pumped into the donor. Electrodes were placed on the splenic nerve and the spleen was bathed in liquid paraffin at 370 C. The nerve was stimulated with 50 V pulses of 0.5 msec duration at 10/sec. Extraction procedures. The procedures are outlined in Fig. 1

Distribution of Prostaglandins in Human Tissues

“…The work of Ramwell et al (1965) with the phrenic nerve diaphragm preparation has already been quoted; more recently the same group have demonstrated release of prostaglandins from adrenals stimulated with acetylcholine (Ramwell, Shaw, Douglas & Poisner, 1966). Davies, Horton & Withrington (1966) have shown that electrical stimulation of splenic nerve leads to release of prostaglandins into splenic venous blood, and Shaw (1966) has found a release of prostaglandins from adipose tissue in vitro in response to sympathetic nerve stimulation. These findings and our own work do not link prostaglandins with any particular component of the nervous system, as the substances may be found in the central and peripheral nervous system, including sympathetic and parasympathetic.…”

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).…”

Pyrogen fever and prostaglandin‐like activity in cerebrospinal fluid

“…In previous experiments on the release of prostaglandins from different tissues in response to a variety of stimuli it was shown that the amounts released within a short period were far in excess of those present in the unstimulated tissues. This suggested rapid synthesis (Ramwell, Shaw, Douglas & Poisner, 1966; Davies, Horton & Withrington, 1968). In fact, as expressed by Piper & Vane (1971) prostaglandin release can often be equated with prostaglandin synthesis.…”