Related Experiment Video
Updated: Feb 6, 2026
A Procedure to Observe Context-induced Renewal of Pavlovian-conditioned Alcohol-seeking Behavior in Rats
Published on: September 19, 2014
Testicular and epididymal toxicity induced by benzo(a)pyrene, alcohol, and their combination in Wistar rats
K Pratap Reddy1,2, P Sreenivasula Reddy2
1Department of Biotechnology , Sri Venkateswara University , Tirupati - 517502 , India.
Abstract:
Alcoholism and cigarette smoking are pervasive problems that have been implicated in human health. In this study, independent and combinative toxicities of alcohol and benzo(a)pyrene (BaP) were tested for reproductive toxicity in rats. Male Wistar rats were exposed to BaP (100 μg per kg body weight) on alternative days and alcohol (2 g per kg body weight per day) daily, either individually or in combination for 60 days. Exposure to BaP or alcohol significantly decreased the fertility index and reduced the number of implantations associated with elevated pre- and post-implantation losses. The relative weights of testes, epididymis, seminal vesicles, and prostate gland were significantly decreased in BaP or alcohol administered rats. Exposure to BaP or alcohol significantly decreased daily sperm production, sperm density, percentages of motile, viable, HOS-tail swelled sperm, testicular 3β- and 17β-hydroxysteroid dehydrogenase activity levels, mRNA levels of steroidogenic acute regulatory protein, and serum testosterone levels. Further, in silico studies revealed the binding of BaP at the hydrophobic tunnel of StAR protein. Additional studies disclosed stable interactions of BaP with the amide group of ASN150 and the hydroxyl group of THR263 by forming three hydrogen bonds. Our results also showed that treatment of rats with BaP or alcohol caused a marked increase in levels of superoxide anions, hydrogen peroxide, and lipid peroxidation in testis and epididymis. Conversely, glutathione levels and activity levels of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase in testis as well as epididymis decreased significantly in the experimental rats. Under the same conditions, increased fragmented DNA levels were observed in sperm. The results of the present study indicate that exposure to BaP or alcohol adversely affected the male reproductive functions, which may be, at least in part, due to androgen deficiency and/or oxidative stress-related mechanisms. Consistently, the present results also showed higher reproductive toxicity upon exposure to combinations of BaP and alcohol than upon their individual treatments. Therefore, this combination was classified as additive and synergistic responses of BaP and alcohol.
Related Concept Videos
02:37Oxidation of Alcohols
The process of oxidation in a chemical reaction is observed in any of the three forms:
02:29Ethers from Alcohols: Alcohol Dehydration and Williamson Ether Synthesis
Ethers can be prepared from organic compounds by various methods. Some of them are discussed below,
Preparation of Ethers by Alcohol Dehydration
In this method, in the presence of protic acids, alcohol dehydrates to produce alkenes and ethers under different conditions. For example, in the presence of sulphuric acid, dehydration of ethanol at 413 K yields ethoxyethane, whereas it yields ethene at 443 K.
02:31Protection of Alcohols
Protection
It defines a protecting group as the masking agent to make the more reactive species inert to a given set of conditions. This concept is depicted via the illustration of liquid flow through different outlets in an assembly of pipes. The analogy helps to understand the role...
01:26Toxic Reactions: Overview
Toxicity falls into two primary categories: local and systemic.
Local toxicity appears at the exposure site, such as protein denaturation caused by caustic substances.
In contrast, systemic toxicity requires the toxic agent's absorption and distribution,...
01:38Preparation of Alcohols via Substitution Reactions
Alcohols can be synthesized from alkyl halides via nucleophilic substitution reactions. The highly polar carbon-halogen bond in the substrate makes halide a good leaving group. The hydroxide ion or water can act as a nucleophile to take the place of halide and form an alcohol. The substitution reactions occur via two different reaction pathways, SN1 or SN2, depending on the nature of carbon attached to the halide.
Primary alcohols are synthesized from primary alkyl halides, and the...
01:17Esters to Alcohols: Hydride Reductions
Lithium aluminum hydride is a source of hydride ions and functions as a nucleophile. The mechanism proceeds in three steps. Firstly, the nucleophilic hydride ion attacks the carbonyl carbon of the ester to form a tetrahedral intermediate. Subsequently, the carbonyl group re-forms,...