Abstract
Vascular and motor responses in the rectum to pelvic nerve stimulation are described in the anaesthetized cat and compared with corresponding effects observed in the colon. The responses comprise a cholinergic and a non-cholinergic component, and an attempt has been made to elucidate the latter. Pelvic nerve stimulation evoked a pronounced and well maintained vasodilator response in the rectum whereas that in the colon was transient. Maximal vasodilatation occurred at much lower stimulus frequencies in the rectum (2-4 Hz) than it did in the colon (8-16 Hz) and maximal blood flow under these conditions was also greater in the rectum (greater than 200 ml 100 g-1 min-1) than the colon (less than 150 ml 100 g-1 min-1). Muscarinic blockade further curtailed the colonic vasodilator response to pelvic nerve stimulation, whereas the rectal dilatation was only slightly reduced in the presence of atropine. Pelvic nerve stimulation caused a substantial release of vasoactive intestinal polypeptide (VIP) from the rectum, which was related both in magnitude and duration to the vasodilatation. Intra-arterial infusions of VIP, which reproduced this rise in rectal venous VIP concentration, caused a rectal vasodilator response which closely resembled that during pelvic nerve stimulation after cholinergic blockade. The rectal vasculature was estimated to be 50-100 times more sensitive to VIP than the colonic vasculature. VIP therefore seems to be the most likely putative neurotransmitter responsible for non-cholinergic rectal vasodilatation. Stimulation of the pelvic nerves also caused rapid contractile motor responses before, and more gradual motor responses after, muscarinic blockade in both the colon and rectum, in the latter preceded by a non-cholinergic relaxation. These patterns of motor activity largely confirm previous results. Infusions of substance P effectively mimicked the non-cholinergic contractile motor responses but failed to demonstrate significant release of this peptide during pelvic nerve stimulation in the present experiments. However, substance P is rapidly inactivated and might possibly be involved in these responses. Stimulation of the pelvic nerves in bursts at high frequencies (up to 80 Hz), simulating a discharge pattern observed electrophysiologically in vivo, was effective in eliciting all the above responses, with the exception of the colonic contraction.
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Selected References
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- Andersson P. O., Bloom S. R., Edwards A. V., Järhult J. Effects of stimulation of the chorda tympani in bursts on submaxillary responses in the cat. J Physiol. 1982 Jan;322:469–483. doi: 10.1113/jphysiol.1982.sp014050. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Andersson P. O., Bloom S. R., Edwards A. V. Parotid responses to stimulation of the parasympathetic innervation in bursts in weaned lambs. J Physiol. 1982 Sep;330:163–174. doi: 10.1113/jphysiol.1982.sp014335. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Andersson P. O., Bloom S. R., Järhult J. Colonic motor and vascular responses to pelvic nerve stimulation and their relation to local peptide release in the cat. J Physiol. 1983 Jan;334:293–307. doi: 10.1113/jphysiol.1983.sp014495. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bloom S. R., Edwards A. V. Vasoactive intestinal peptide in relation to atropine resistant vasodilatation in the submaxillary gland of the cat. J Physiol. 1980 Mar;300:41–53. doi: 10.1113/jphysiol.1980.sp013150. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Buffa R., Capella C., Fontana P., Usellini L., Solcia E. Types of endocrine cells in the human colon and rectum. Cell Tissue Res. 1978 Sep 5;192(2):227–240. doi: 10.1007/BF00220741. [DOI] [PubMed] [Google Scholar]
- De Groat W. C., Booth A. M., Milne R. J., Roppolo J. R. Parasympathetic preganglionic neurons in the sacral spinal cord. J Auton Nerv Syst. 1982 Jan;5(1):23–43. doi: 10.1016/0165-1838(82)90087-x. [DOI] [PubMed] [Google Scholar]
- Eklund S., Jodal M., Lundgren O., Sjöqvist A. Effects of vasoactive intestinal polypeptide on blood flow, motility and fluid transport in the gastrointestinal tract of the cat. Acta Physiol Scand. 1979 Apr;105(4):461–468. doi: 10.1111/j.1748-1716.1979.tb00111.x. [DOI] [PubMed] [Google Scholar]
- FOLKOW B. Impulse frequency in sympathetic vasomotor fibres correlated to the release and elimination of the transmitter. Acta Physiol Scand. 1952;25(1):49–76. doi: 10.1111/j.1748-1716.1952.tb00858.x. [DOI] [PubMed] [Google Scholar]
- Fahrenkrug J., Haglund U., Jodal M., Lundgren O., Olbe L., de Muckadell O. B. Nervous release of vasoactive intestinal polypeptide in the gastrointestinal tract of cats: possible physiological implications. J Physiol. 1978 Nov;284:291–305. doi: 10.1113/jphysiol.1978.sp012541. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fasth S., Hultén L., Nordgren S. Evidence for a dual pelvic nerve influence on large bowel motility in the cat. J Physiol. 1980 Jan;298:159–169. doi: 10.1113/jphysiol.1980.sp013073. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fasth S., Hultén L., Nordgren S., Zeitlin I. J. Studies on the atropine-resistant sacral parasympathetic vascular and motility responses in the cat colon. J Physiol. 1981 Feb;311:421–429. doi: 10.1113/jphysiol.1981.sp013594. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grände P. O., Järhult J., Mellander S. Methods for gravimetric registration of changes in tissue volume. Acta Physiol Scand. 1974 Jun;91(2):211–215. doi: 10.1111/j.1748-1716.1974.tb05678.x. [DOI] [PubMed] [Google Scholar]
- Hellström P. M., Rosell S. Effects of neurotensin, substance P and methionine-enkephalin on colonic motility. Acta Physiol Scand. 1981 Oct;113(2):147–154. doi: 10.1111/j.1748-1716.1981.tb06875.x. [DOI] [PubMed] [Google Scholar]
- Hultén L. Extrinsic nervous control of colonic motility and blood flow. An experimental study in the cat. Acta Physiol Scand Suppl. 1969;335:1–116. [PubMed] [Google Scholar]
- Langley J. N., Anderson H. K. On the Innervation of the Pelvic and Adjoining Viscera: Part I. The Lower Portion of the Intestine. J Physiol. 1895 May 20;18(1-2):67–105. doi: 10.1113/jphysiol.1895.sp000558. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mitchell S. J., Bloom S. R. Measurement of fasting and postprandial plasma VIP in man. Gut. 1978 Nov;19(11):1043–1048. doi: 10.1136/gut.19.11.1043. [DOI] [PMC free article] [PubMed] [Google Scholar]
