الفهرس 
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Abstract
The present work aims at investigating the immunotoxicity of two pesticides widely used in Egypt; namely lampcon and Saturn. Lampcon is a synthetic pyrethroid insecticide and acaricide manufactured by Healthy Life Pharma used to control a wide range of pests in a variety of applications. While, saturn is a carbamate herbicide manufactured by Kumiai Chemical Industry Co., Ltd. Japan applied mainly on rice, wheat, canola, peanut, soybean, cotton, corn and sugar cane.
The oral LD50 of the two pesticides was firstly determined followed by studying the possible adverse effects of lampcon and saturn on the humoral immune response of male rats. Thirty young adult male rats were used for the humoral immune study.
Animals were classified into 3 groups: the first group received no treatment and served as control; the second group received 1/10th oral LD50 of lampcon (11.2
mg/kg equivalent to 168 ppm in food) daily for 60 days and the third group received 1/10th oral LD50 of saturn (282 mg/kg equivalent to 4230 ppm in food) daily for 60 days. Control and treated rats were immunized by I.P injection of 0.5 ml of a 20% SRBC suspension at the 40th day of insecticide exposure. A second (booster) dose was given 15 days after the first immunization. Animals were then sacrificed 5 days after injection of the booster dose for determination of body weight, the weights of liver, spleen and thymus, total and differential leukocytic counts, electrophoretic pattern of blood proteins, hemolysin antibody titer, serum immunoglobulin levels and histopathology of liver, spleen, thymus and lymph nodes .
The toxic effects of lampcon and saturn on the cellular immune response of male rats were also studied. Thirty male rats were classified and treated with the two pesticides as mentioned previously in humoral immunity assessment. One day before the end of chemical exposure (on 59th day), intradermal injection of 0.5 ml animal of a 20 % SRBC suspension was performed. Animals were used for studying the delayed-type hypersensitivity response by measuring the diameter and thickness of skin reactions 24 and 48 hours after the challenge with SRBCs.
Investigation of blood leukocyte function by assessment of oxidative stress in blood leukocytes (lipid peroxide ”MDA” and reduced glutathione levels; catalase glutathione reductase and glutathione peroxidase activities) and the phagocytic activity of neutrophils was also done.
The oral LD50 of lampcon was determined to be 112.2 mg/kg body weight.
Symptoms of intoxication were observed few minutes after administration including: piloerection, ataxia, choreoathetosis, salivation, lacrimation and decreased motor activity. The oral LD50 of Saturn was found to be 2818.38 mg/Kg of body weight. Signs of intoxication included loss of appetite, squinting excessive production of saliva, watery eyes, hairs standing on end, labored breathing, reduced body temperature, incoordination, depression and rapid muscle twitching.
Treatment of rats with lampcon did not affect the body weight of rats while a significant reduction in body weight of saturn-treated rats was recorded after 4, 6 and 8 weeks.
Exposure of rats to lampcon did not affect liver weight; however, the weights of spleen and thymus were significantly reduced. In saturn- treated rats, a significant reduction in liver weight was noted in addition to decrease in the weights of spleen and thymus.
Lampcon and saturn exposure caused significant reductions in total leukocytic
and lymphocytic counts while the neutrophils showed significant increase.
Serum total protein and serum albumin level were significantly reduced in
lampcon and saturn treated groups. The concentration of serum total globulin in both
lampcon and saturn-treated groups showed no significant differences. The
albumin/globulin ratio decreased significantly only in the saturn treated rats.
A significant reduction in the level of α1 globulin was recorded in both lampcon
and saturn treated groups, however, the changes in the concentrations of α2 globulin
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were non-significant. A significant elevation in the level of β globulin was observed
in both lampcon and saturn treated groups. Concerning the serum concentrations of γ
globulin in lampcon and saturn treated groups, significant reductions were recorded.
The hemolysin antibody titer and the level of IgM and IgG showed significant
reduction in lampcon and saturn - treated rats. The diameter of skin reaction
measured after 24 and 48 hours (post- intradermal injection of 0.5 ml/animal of a 20
% SRBC suspension) was significantly reduced due to lampcon and saturn treatment.
The thickness of skin reaction measured after 24 hours was significantly decreased
due to lampcon and saturn treatment. After 48 hours, only saturn -treated animals
showed significant decrease.
Treatment of male rats with lampcon and saturn induced oxidative stress in
leukocytes as indicated by significantly elevated levels of MDA and decreased
reduced glutathione level and catalase and glutathione peroxidase activities. The
activity of leukocytic glutathione reductase was only significantly inhibited by
lampcon treatment. The phagocytic activity of neutrophils showed significant
reduction in saturn-treated group only.
The liver of lampcon treated rats showed congested central vein, Kupffer cell
hyperplasia, various degrees of hydropic degeneration, formation of newly formed
bile duct, sporadic cell necrosis and infiltration of portal area by lymphocytes. Spleen
periarterial lymphoid sheath showed lymphoid exhaustion. The thymus revealed
necrosis in cortical lymphocyte and depletion in medulla. The ileum and mesenteric
lymph nodes showed lymphoid depletion.
Saturn produced histopathological changes in lymphoid organs. Liver showed
Kuppfer cell hyperplasia, congestion of sinusoids and central vein, and sporadic and
single cell necrosis. Spleen revealed necrosis and depletion of lymphocytes in
periarterial lymphoid sheath “white pulp”. The thymus gland showed congestion and
single cell necrosis. The ileum and mesenteric lymph nodes showed lymphoid
depletion.