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RESEARCH ARTICLE

Cellular changes in the hamster testicular interstitium with ageing and after exposure to short photoperiod

E. Beltrán-Frutos A , V. Seco-Rovira A , C. Ferrer A , J. F. Madrid A , F. J. Sáez B , M. Canteras C and L. M. Pastor A D
+ Author Affiliations
- Author Affiliations

A Department of Cell Biology and Histology, Ageing Institute, IMIB-Arrixaca, Regional Campus of International Excellence ‘Campus Mare Nostrum’, University of Murcia, 30100 Murcia, Spain.

B Department of Cell Biology and Histology UFI11/44, School of Medicine and Dentistry, University of the Basque Country, UPV/EHU, Barrio Sarriena, s/n, 48940 Leioa, Biscay, Spain.

C Department of Statistics, School of Medicine, Regional Campus of International Excellence ‘Campus Mare Nostrum’, University of Murcia, 30100 Murcia, Spain.

D Corresponding author. Email: bioetica@um.es

Reproduction, Fertility and Development 28(6) 838-851 https://doi.org/10.1071/RD14117
Submitted: 3 April 2014  Accepted: 9 October 2014   Published: 2 December 2014

Abstract

The aim of this study was to evaluate the cellular changes that occur in the hamster testicular interstitium in two very different physiological situations involving testicular involution: ageing and exposure to a short photoperiod. The animals were divided into an ‘age group’ with three subgroups – young, adult and old animals – and a ‘regressed group’ with animals subjected to a short photoperiod. The testicular interstitium was characterised by light and electron microscopy. Interstitial cells were studied histochemically with regard to their proliferation, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP in situ nick end labelling (TUNEL+) and testosterone synthetic activity. We identified two types of Leydig cell: Type A cells showed a normal morphology, while Type B cells appeared necrotic. With ageing, pericyte proliferation decreased but there was no variation in the index of TUNEL-positive Leydig cells. In the regressed group, pericyte proliferation was greater and TUNEL-positive cells were not observed in the interstitium. The testicular interstitium suffered few ultrastructural changes during ageing and necrotic Leydig cells were observed. In contrast, an ultrastructural involution of Leydig cells with no necrosis was observed in the regressed group. In conclusion, the testicular interstitium of Mesocricetus auratus showed different cellular changes in the two groups (age and regressed), probably due to the irreversible nature of ageing and the reversible character of changes induced by short photoperiod.

Additional keywords: apoptosis, Leydig cell, proliferation, testes, ultrastructure.


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