Guinea Jejunum

Lauterbach, F., Intestinal permeation of nonquatemary amines a study with telenzepine and pirenzepine in the isolated mucosa of guinea pig jejunum and colon, J. Pharmacol. Exp. Ther. 1987, 243, 1121-1130. 

In a cooperation project20 with Professor H. Timmerman, Dr. R. Leurs and coworkers (Vrije Universiteit Amsterdam), we compared the effects of the higher homologues of histamine (i.e. replacement of the ethylene side chain by n-propylene, n-butylene, n-pentylene etc.) in mouse brain cortex slices and in guinea-pig jejunum. 

Most studies of the local actions of opioids on the intestinal mucosa have utilized muscle-stripped sheets of ileal mucosa with attached submucosa mounted in Ussing flux chambers. Peptidase-resistant enkephalin derivatives such as DPDPE decrease short-circuit current, an electrical measure of active transepithelial ion transport, across isolated mucosal sheets from the guinea pig ileum [46,127,128], rabbit ileum [129-131], mouse jejunum [132], and pig distal jejunum/ileum [133]. This effect, which occurs after the application of opioid agonists to the serosal aspect of epithelial sheets, is due to an increase in electroneutral salt absorption and a decrease in electrogenic chloride secretion [46,132,133], In contrast to enkephalin derivatives, opiate alkaloids have limited effects on active transepithelial transport of ions [69]. Pretreat-... 

Absorption of lithium from guinea pig jejunum has been studied using an isolated mucosal preparation from which the underlying mus-cularis mucosae has been stripped (164). Absorption was shown to occur via a paracellular route and was unaffected by metabolic inhibitors or antidepressant, neuroleptic, or antiinflammatory drugs (165-167). These findings confirmed earlier work using everted sacs prepared from rat intestine (168, 169). The passive nature of lithium uptake into both kidney slices and isolated guinea pig intestinal epithelial cells has also been reported (170, 171). 

Figure 4. Structures of newly developed histamine analogues. The Hg receptor activity at the guinea-pig jejunum is indicated between parentheses. The dose-response curves for (R)-a-methylhistamine (RAMH), as measured as the inhibition of electrically-induced neurogenic contractions of the guinea-pig jejunum, in the absence or presence of three different concentrations of impentamine (VUF 4702) are shown.

Fundus) tine Rabbit lung Rabbit stomach (Pylorus) Guinea-pig liver Rat jejunum Rat stomach (non-glandular) Guinea-pig lung... 

Leukotriene Actions in the Gastrointestinal System - Large species differences have been found in the response of gastrointestinal tissue to sulfidcpeptide leukotrienes. Human gastrointestinal muscle (ileum, stonach, jejunum, colon) does not contract to SRS-A from guinea pig lung. In contrast, both LTC, and ITD contract the rat stomach and colon but not the duodenum or ileum. 4 dd E, produce... 

In the guinea-pig jejunum, co-conotoxin GVIA blocked only partially (33%) the inhibitory NANC transmission upon electrical stimulation. This was also the case at the taenia caecum (20% inhibition) [154]. In the proximal duodenum the NANC transmission was insensitive to co-conotoxin GVIA [155]. 

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