188 REDVET - Revista electrónica de Veterinaria - ISSN 1695-7504 Vol 23, No. 3 (2022) http://www.veterinaria.org Article Received: 25 March 2022; Revised: 15 April 2022; Accepted: 17 May 2022; Publication: 02 July 2022 Physiological Effects of Nano L-carnitine on the Gonadal Pathway in Adult Male Rats Exposed to Lead Acetate Hayder Talib Mahdi 1,2 , Dr. Rashad Fadhil Ghadhban 1 1-Department of Physiology, Pharmacology and Biochemistry, College of Veterinary Medicine, University of Basrah, Basrah, Iraq 2- Department of Physiology, College of Medicine, Al-Ameed University, Karbala, Iraq Email : hayder@alameed.edu.iq Abstract: This study was conducted to determine the role of L-Carnitine (LC) and Nano L-Carnitine protected male rats from testicular toxicity caused by lead acetate (PbAc) by investigating the effectiveness of biosynthesized L- Carnitine nanoparticles (LC-NPs) on the fertility status of male rats. LC-NPs were synthesized, which could be by encapsulating l-carnitine in Chitosan (CS)-tripolyphosphate (TPP)-based nanoparticles (NP); Materials and methods: six groups of adult Wistar albino rats (10 per group) were divided as follows: The first group (control group): received orally Distilled water. the second group: received orally lead Acetate at a dose of 30 mg/kg of body weight daily for 30 days. third group: received (lead acetate 30mg/kg b.w.for 30 days + L- carnitine 100mg/ kg b.w. /day for two months). fouth group received lead acetate 30mg/kg b.w.for 30 days +Nano L-carnitine 100mg/ kg b.w./day for two months). fifth group: received L-Carnitine orally at a dose of 100mg/ kg b.w./day for two months. sixth group: received L-Carnitine-NPs orally at 100mg/ kg b.w./ day for two months. Results: a significant increase (P<0.05) in the testosterone hormone levels in the lead acetate+ Nano L-Carnitine group compared with the lead acetate group. While showed decreased levels of FSH and LH in the lead acetate+ Nano L-Carnitine group compared with the lead acetate group. On the other hand, The results showed a significant increase (P<0.05) in the percentage of count and motility in group three(lead acetate+l-carnitine) and group four (lead acetate + nano l-carnitine) compared with group two (lead acetate). Show better improvements in the percentage in group four. Also showed a significant (P<0.05) decrease in the rate of dead sperm and abnormal morphology in group three and group four compared with group two (lead acetate). Histopathological changes were marked in testes; these changes included damage. Severe degeneration and sloughing of germinal epithelium with basement membrane disarrangement; no spermatid in seminiferous tubule lumens accompanied with atrophy and irregularity, vacuolization with few spermatogonia in seminiferous tubule lumens those changes reduced or disappeared in the treated groups. Keywords: nanoparticles, chitosan, L-carnitine, lead acetate, sperm parameters, testes, reproductive hormones. Introduction: Nanobiotechnology is today regarded as the foundation for advancing all life sciences and biomedical research sectors, including diagnostics, treatment, and medication delivery (1). Many factors restrict the efficiency of many therapies, including low bioavailability, in vivo low stability, solubility, intestinal absorption difficulties and therapeutic effectiveness, side effects, and exceeding the safe dose concentrations of many of these therapies (2). In most cases, only a fraction of the required dosage reaches the intended target (3). According to its kinetics and biological features, the majority of the drug is distributed throughout the