The photoperiod and heat stress effects on histometrical structure of rat prostate gland

Abstract

BACKGROUND: There is not enough information about theeffects of heat stress and photoperiod on different lobes structure.OBJECTIVES: The present study aims at determining thehistological changes and the rate of changes in each lobes of ratprostate, affected by photoperiod changes and heat stress.METHODS:To this end, 15 adult male wistar rats were divided tothree groups: 1. the control group in which the rats were kept in12L: 12D and 25°C temperature condition, 2. the heat stressgroup in which the rats were kept in 12L: 12D and 42+1 °Ctemperature condition for 4 to 5 hours per day, and 3. thephotoperiod group in which the rats were kept in 16L: 8D and25°C temperature condition. After 30 days, samples were takenfrom different lobes and sections with 5 to 6μ thickness weremade and stained by HE however, it increased by photoperiod.The maximum changes were seen in ventral lobe. The epithelialthickness, lumen diameter, and number of secretory units alsoincreased by photoperiod (16L:8D), but it decreased by heatstress. The number of secretory cells were increased by heatstress because the cell size decreased; however, they decreasedby long photoperiod regime. The number of folded secretoryunits increased by photoperiod, while heat stress has an adverseeffect (p<0.001). The serum testosterone increased by longphotoperiod and decreased by heat stress (p<0.01).CONCLUSIONS: This study shows that long photoperiod hasimportant effects on increasing the rat prostate parenchyma andits activity.