%0 Journal Article
%T Seasonal Changes in Testes Vascularisation in the Domestic Cat (Felis domesticus): Evaluation of Microvasculature, Angiogenic Activity, and Endothelial Cell Expression
%A Gra£¿a Alexandre-Pires
%A Lu¨ªsa Mateus
%A Catarina Martins
%A Gra£¿a Ferreira-Dias
%J Anatomy Research International
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/583798
%X Some male seasonal breeders undergo testicular growth and regression throughout the year. The objective of this study was to understand the effect of seasonality on: (i) microvasculature of cat testes; (ii) angiogenic activity in testicular tissue in vitro; and (iii) testicular endothelial cells expression throughout the year. Testicular vascular areas increased in March and April, June and July, being the highest in November and December. Testes tissue differently stimulated in vitro angiogenic activity, according to seasonality, being more evident in February, and November and December. Even though CD143 expression was higher in December, smaller peaks were present in April and July. As changes in angiogenesis may play a role on testes vascular growth and regression during the breeding and non-breeding seasons, data suggest that testicular vascularisation in cats is increased in three photoperiod windows of time, November/December, March/April and June/July. This increase in testicular vascularisation might be related to higher seasonal sexual activity in cats, which is in agreement with the fact that most queens give birth at the beginning of the year, between May and July, and in September. 1. Introduction The study of the vasculature of the testis has attracted scientists¡¯ attention for many centuries, especially at the end of the 19th and throughout the 20th century. This research has been performed in a large variety of animal species such as rat, mouse, rabbit, guinea pig, dog, ram, bull, boar, horse, marsupials, man, and other primates [1¨C4]. It has been long known that the physiologic role of the pampiniform plexus, on thermoregulation of the testes. This is a highly efficient countercurrent heat exchanger in which the arterial blood is precooled before it reaches the testis, while venous blood is warmed to body temperature before it returns to the abdomen [5]. It is nevertheless very rare to find references on the vasculature of cat testes (Felis domesticus). Angiogenesis is physiologically modulated through a dynamic balance between the production and release of angiogenic/mitogenic growth factors or antiangiogenic/anti-mitogenic substances [6¨C9]. In the adult, physiological angiogenesis is mostly restricted to the female reproductive tract during the ovarian/uterine cycle [10¨C13]. Nevertheless, in the male, physiologic gonadal angiogenesis has also been described. Testicular angiogenesis is known to increase during testicular recrudescence in seasonal breeders such as the hamster [14] or to decrease in response to food restriction in
%U http://www.hindawi.com/journals/ari/2012/583798/