In order to investigate the effects of dimethylamino substituent at postion 2 of the dihydropyridine nucleus on its activity, dialkyl 1,4-dihydro-2-[2-(dimethylamino) ethyl]-6-methyl-4-(1-benzyl-2-alkylthio-5-imidazolyl)-3,5-pyrdinedicarboxylates (6a-f) were synthesized. The synthesis was started from dialkyl 1,4- dihydro-2,6-dimethyl-4-(1-benzyl-2-alkylthio-5-imidazolyl)-3,5-pyridinedicarboxylates (5a-f) which their synthesis and effects as calcium channel antagonist on guinea-pig ileum has been reported previously. Rabbit jejunum was used to determine the relaxant or antagonistic activity of the synthesized compounds. Some of the compounds (6c-e) inhibited the spontaneous contractile activity of jejunum, dose-dependently and completely, while high-K+ contracted tissues were relaxed partially.

In order to investigate the effects of dimethylamino substituent at position 2 of the diliydropyridine nucleus on activity, starting from dialkyl 1,4- dihydro -2,6- dimethyl -4- (1-benzyl- 2- alkylthio -5-imidazolyl) -3,5- pyridinedicarboxylates (5a-f) which their synthesis and effects as calcium channel antagonist on guinea-pig ileum has been reported previously, dialkyl 1,4-diliydro-2- [2- (dimethylamino) ethyl]-6-methyl -4- (1-benzyl-2- alkylthio-5-imidazolyl) - 3,5- pyridinedicarboxylates (6a-f) were synthesized.Rabbit jejunum was used to determine the relaxant or antagonistic activity of the test compounds. The test compounds (6c-e) inhibited the spontaneous contractile activity dose-dependently and completely, while high-K+ contracted tissues were relaxed partially.

Background: Nitric Oxide (NO) is a very important signaling molecule which acts as a regulator of many physiological processes in many tissues including epithelial cell of gastrointestinal tract. In this study we investigated the effects of L-Arginine as a NO progenitor and L-NAME as a NO inhibitor on epithelial cell number and height of jejunum in female rats. Materials and methods: 40 female rats were divided into 5 groups, containing 8 rats in each group. Except the control group, the other groups received normal saline (2 ml/kg), L-Arginine (200mg/kg), L-NAME (20mg/kg) and a mixture of two substances for L-Arginine & L-NAME group intraperitoneally for 3 days. 2 weeks later after anesthesia with ether, jejunum was expelled out and after tissue processing and staining with H&E method, the changes were assessed via light microscopy. Cell number and height were evaluated using Image Tools3 Microsoft. Statistical analysis was made by One-Way ANOVA followed by Tukey post hoc test to evaluate the statistical significance between different groups. A value of p< 0. 05 was considered statistically significant. Results: There was a significant increase in the cell number and height of jejunal epithelium in L-Arginine group (P<0. 05). Whereas no significant difference was observed between L-NAME, L-Arginine +L-NAME and control, Normal Saline groups. Conclusion: L-Arginine can result in proliferation of jejunum epithelial cells whereas L-NAME has no effect on these cells.

For this study the jejuni of 50 adult (2-4 years), apparently healthy Iranian river buffaloes were collected from the abattoir for gross morphology, histomorphology, and histomorphometry. Our statistical analysis revealed that, there are significant (P<0.001) differences in the lengths, external diameters, internal diameters, external circumferences, internal circumferences as well as wall thicknesses of jejunum between all of the animals under study. Our macroscopic investigations also revealed that, in these buffaloes, jejunal Peyer’s patches (jejpp) are not grossly visible in the mucosa of this part of gut. The histomorphology of submucosa revealed a pear shaped jejpp through the whole length of the jejuni at mesenteric as well as antimesenteric parts. The distributions of the jejpp in the middle and posterior parts of guts were greater than in the anterior part. The mean thickness of the mucosal glandular region was highly significant (P<0.001) between the anterior, middle, and posterior regions. There were no significant differences (P>0.05) in lengths as well as thicknesses of jejunal villi between the 3 different regions. The mast cells distributions were highly significant (P<0.001) between the superficial and deep regions of jejunal tunicae mucosae in all buffaloes. There were also highly significant (P<0.001) differences in the distribution of goblet cells between the superficial and deep regions of jejunal mucosa, and their population was more in the superficial than in the deep region.