Comparative evaluation of sterilizing potential of intratesticular chemosterilants in male albino rats

Abstract

Objective: To investigate the sterilizing potential of zinc gluconate, calcium chloride (CaCl₂) and cadmium chloride (CdCl₂) following a single intratesticular administration in adult male rats.

Methods: 60 adult male Wistar albino rats (Rattus norvegicus) weighing 160-200 g and aged 5-6 months randomly received a single intratesticular injection of normal saline (Group A), zinc gluconate 13.3 mg/mL plus L-Arginine (Group B), 20% CaCl₂ (Group C), and CdCl₂ 0.5 mg/kg body weight plus ethylenediaminetetraacetic acid (EDTA) (Group D), respectively, along the entire route from the caudoventral aspect of each testis. They were euthanized up to 180 days to evaluate reproductive tract toxicology.

Results: The reproductive organ weights were markedly reduced, with testes severely atrophied in group B, pea-sized and stony hard in group C, and moderately reduced in group D. Azoospermia was evident in groups B and C, while sperm concentration was reduced to <1 million/mL with zero sperm motility in group D. Rats of groups B and C failed to show mounting and copulatory behaviour. A completely disorganized mesh of cellular elements was observed in the seminiferous tubules of group B, while pyknotic germ cell and arrest of spermatogenesis, exfoliated germ cells, occasional syncytial bodies and smaller Leydig cells were evident in groups C and D. Significantly reduced testosterone levels, increased luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels, returned to normal after 90 days in group D.

Conclusions: Zinc gluconate and CaCl₂ injections severely affected the reproductive organs and libido and rats treated with CdCl₂ exhibited diminished spermatogenesis with normal libido. Thus, the need-based selection of intratesticular agents should consider their distinct effects on spermatogenesis, libido, and hormonal balance for achieving targeted sterilization outcomes.

Keywords

Zinc gluconate / Calcium chloride / Cadmium chloride / Intratesticular chemosterilization / Azoospermia / Male rats / Reproductive toxicity / Canine population control

Conflict of interest statement

All authors declare no significant competing interests.

Acknowledgments

The infrastructural facilities provided by the Head of the Department are gratefully acknowledged. Prof. Nirmal Kumar Lohiya is thankful to the National Academy of Medical Sciences, India for awarding, Emeritus Professorship. The ultrastructural studies were carried out at the electron microscope facility of the Malaviya National Institute of Technology, Materials Research Centre (MRC), JLN Marg, Malviya Nagar, Jaipur, Rajasthan, India.

Funding

The study was financially assisted to Timanshi Chansoriya of the fellowship grant of UGC-NFPwD, New Delhi sanctioned vide UGC F. No. 01-01/2019-Sch dated 06.11.2020 (Serial No. 352 ID: NFPWD-2018-20-UTP-6522).

Authors’ contributions

Abdul Salam Ansari designed the study. Timanshi Chansoriya and Barkha Khilwani conducted the experiment, analyzed data and drafted the manuscript. Abdul Salam Ansari and Nirmal Kumar Lohiya finally approved the final version to be published. All authors read and approved the final manuscript.

Publisher’ s Note

The Publisher of the Journal remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

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