ISSN 2756-3707
International Journal of Histology and Cytology ISSN 2756-3707 Vol. 13 (4), pp. 001-012, April, 2025. Available online at www.internationalscholarsjournals.org © International Scholars Journals
Full Length Research Paper
Immunohistochemical Analysis of Angiotensin II AT1 and AT2 Receptor Isoforms in Sprague-Dawley Rat and Meriones crassus Adrenal Glands
Al-Qattan, K., Mansour, M. H.* and Al-Naser, M.
Department of Biological Sciences, Faculty of Science, Kuwait University, P. O. Box 5969, Safat 13060, Kuwait.
Accepted 14 Jauary, 2024
Employing specific polyclonal anti-AT1 and anti-AT2 antibodies, AT1 and AT2 receptor expression was immunohistochemically demonstrable within adrenal tissues in Sprague-Dawley rats and the desert rodent Meriones crassus. Among adrenal cortical zones in rats, AT1 receptor labeling was evident in zona glomerulosa and zona reticularis. In contrast, AT1 receptor labeling was confined to the zona glomerulosa and the deep zona fasiculata in Meriones crassus. AT1 receptor labeling was, however, equally observed among ganglion and chromaffin cells constituting the adrenal medulla of both animal models. AT2 receptor labeling was faint in all adrenal regions in rats. However, intensity was high in the deep zona fasiculata, and medullary chromaffin and ganglion cells in Meriones crassus. Two-dimensional Western blotting, in the presence or absence of endoglycosidase-F, revealed that structurally distinct spectra of AT1 and AT2 receptor isoforms are expressed in the adrenal tissues of each animal model. These spectra were constituted by molecular isoforms with distinct patterns of charge microheterogeneity unique to each receptor type in each animal model. In both species, heterogeneity of AT1 and AT2 receptor isoforms may be attributed in part to differential post-translational glycosylation mechanisms of the receptor polypeptide backbones, which may be critical in differentially fine-tuning adrenal functions in lab-reared and desert rodents.
Key words: Angiotensin II receptors, adrenal gland, desert rodents, N –linked glycosylation, immunohistochemistry.