The Anatomical RecordVolume 235, Issue 1 p. 87-94 Cardiovascular Biology Comparative ultrastructural morphometric analysis of atrial specific granules in the bat, mouse, and rat C. N. B. Tagoe, Department of Anatomy, Tulane University School of Medicine, New Orleans, Louisiana 70112Search for more papers by this authorA. S. Ayettey, Department of Anatomy, University of Ghana Medical School, Accra, GhanaSearch for more papers by this authorR. D. Yates, Department of Anatomy, Tulane University School of Medicine, New Orleans, Louisiana 70112Search for more papers by this author Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Size, incidence, and volume density of atrial specific granules (ASG) in right atrial cells from five animals each of the rat (average weight 210 g), mouse (average weight 28 g), fruit-eating bat Megaloglossus woermanni (BMW;average weight 35 g), and the insect-eating bat Pipistrellus pipistrellus (BPP; average weight 6 g) have been compared via ultrastructural morphometry. In all three parameters of granule measurement, significantly higher figures were obtained in the rodents than in the bats. However, between the rat and the mouse, as also between the two species of bats, no significant differences were noted in any of the measurements. These results therefore do not support the prevalent view that the number and size of the granules decrease with increase in size of the animal species. The low content of ASG in atrial cells of the bats is probably an indication of low demand for the natriuretic hormone of the granule, because, in such animals, and particularly in flight, conservation of fluid and electrolytes is of paramount importance. This suggests that granule content is adapted to fluid and electrolyte regulation in relation to the functional capacity of the animal. We also observed ASG-like sgtructures in endothelial cells of capillaries of bat tissue but not in rodents. The function of these granules or whether or not they represent atrial specific ones is not clear from the present study. © Wiley-Liss, Inc. The full text of this article hosted at iucr.org is unavailable due to technical difficulties. Please check your email for instructions on resetting your password. If you do not receive an email within 10 minutes, your email address may not be registered, and you may need to create a new Wiley Online Library account. Can\'t sign in? Forgot your username? Enter your email address below and we will send you your username If the address matches an existing account you will receive an email with instructions to retrieve your username