Neurohistological Changes in the Spinal Cord of Albino Rats after Inhalational Exposure to Pyrethroid Based Mosquito Repellent

  • Saim Hasan Associate Professor, Department of Anatomy, SHKM GMC, Nalhar, Mewat Haryana
  • Farida Ahmad Professor, Department of Pharmacology, JNMC, AMU Aligarh
  • S Mubashir Yunus Professor, Department of Anatomy, JNMC, AMU Aligarh
Keywords: Albino Rats, Pyrethroid, Mosquito Repellant


Background: The use of liquid vaporizers as residential insecticides to control the problem of mosquito bites and to prevent adult, newborns and children from deadly vector borne diseases like Malaria, Dengue and chikungunya etc. is ever increasing. These products contain pyrethroid and emit parallethrin vapours when put to use at home. There are numerous side effects of these vapours like allergic sinusitis, difficulty in respiration, sleep disturbance, giddiness, headache, body ache and lethargy but the market for these product decides the outcome of all the research concerned with its safety. Histological studies can establish their toxic effects on Spinal Cord, cervical and lumbar enlargements in the White and Grey matter that forms structural continuity with the CNS. Accordingly the present  study was planned to assess the safety of  pyrethroid based mosquito repellent inhalational use and the histological insult to the spinal cord of  Albino rats.

Methods: Total of twenty albino rats were equally divided into control and experimental group. The experimental group was exposed  to 3.2% w/v prallethrin vapours for total of 12 hours per day for 180 days. The control group rats was exposed to identical situation but without any exposure. The albino rats  were sacrificed after the study period of exposure of 180 days. Spinal cord dissected., tissue processed, sectioned and stained with  haematoxylin, eosin and thionin.

Results: Grey matter of the spinal cord at cervical and lumbar enlargement showed numerous vacuoles with lightly stained cell body of neurons and Nissl’s dissolution with occasional inflammatory cells.

Conclusions: Neurohistological study, inhalational route, neurotoxicity, adult albino rats, prallethrin vapours, spinal cord.


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How to Cite
Hasan S, Ahmad F, Yunus SM. Neurohistological Changes in the Spinal Cord of Albino Rats after Inhalational Exposure to Pyrethroid Based Mosquito Repellent . Int Arch BioMed Clin Res [Internet]. 2019Sep.30 [cited 2021Apr.16];5(3):32-4. Available from: