ABSTRACT
This project was designed to study the possible behavioral effects of propranolol in Wistar rats using both acute and chronic dosage regimens. The study focused on stereotype movement, grooming behavior, drinking behavior, and open-field locomotor activity. Forty-six adult Wistar rats, weighing between 180g and 200g, were obtained and separated into 8 groups, each consisting of 5 rats, with the 9th group consisting of 2 rats for each dose. The rats were acclimatized for two weeks before the commencement of administration. Group 1 (the control group) received a single dose of 0.4ml of normal saline without any other treatment. Group 2 received a single dose of 2mg/kg body weight of propranolol, and similarly, Groups 3 through 8 received 4mg/kg, 8mg/kg, 16mg/kg, 32mg/kg, 64mg/kg, and 128mg/kg body weight of propranolol as single doses, respectively. Group 9 received chronic administration with doses of 2mg/kg, 8mg/kg, and 32mg/kg. In this group, two animals were placed in the same cage and monitored simultaneously for a period of 18 days. In each experimental group, two Wistar rats were observed for one hour in an open-field apparatus. The behaviors were manually scored using a tally counting method, with care taken to observe animals of the same sex, comparable size, weight, and age. Data were analyzed using GraphPad statistical software version 9.5, and comparisons between groups were performed using Student's t-test. Data were presented as mean ± standard error of the mean (SEM), and statistical significance was determined at p ≤ 0.05 The results showed a statistically significant decrease in stereotype movement at lower doses, a statistically significant difference in grooming behavior at higher doses, a statistically significant difference in drinking behavior at some lower and higher doses, and a statistically significant difference in open-field locomotor activity at a low dose. From this work, it can be concluded that propranolol exhibits central nervous system sedative properties, as evidenced by the decrease in observed behavioral activities.
