Introduction: It was aimed to investigate the effect of chronic toluene exposure on amino acid neurotransmitters in the rat brain, corpus striatum. METHODS: Twenty four male Sprague-Dawley rats were divided into one of three groups, control, acute, and chronic. Each groups was for the microdialysis to estimate the changes of amino acid neurotransmitters, aspartate, glutamate, and citrulline before, during, and after 3,000 ppm toluene exposure for 2 hours. RESULTS: The results were as follows; 1) Aspartate and glutamate concentration were generally decreased in the toluene inhalation groups compared with the control group and more significantly decreased in chronic inhalation group than other groups. 2) Citrulline that expressed the activity of nitric oxide synthase and taurine as an inhibitory amino acid showed no significant differences between all groups. Based on these results, it is suggested that the decreasing excitatory amino acids, aspartate and glutamate, are partly contributed to the toxic mechanisms of toluene in rat brain.
Animals ; Aspartic Acid ; Brain* ; Citrulline ; Control Groups ; Corpus Striatum ; Excitatory Amino Acids ; Glutamic Acid ; Humans ; Inhalation ; Male ; Microdialysis ; Neurotransmitter Agents* ; Nitric Oxide Synthase ; Rats* ; Rats, Sprague-Dawley ; Taurine ; Toluene*

PURPOSE: To evaluate MRI and histopathologic findings of toluene inhalation rat brain. MATERIALS AND METHODS: Forty-eight Sprague-Dawley rats, weighing 200-300g, were divided into six groups : the control group and five experimental groups each of eight rats, divided as follows, according to the concentration and duration of inhalation of toluene : 2500 ppm of toluence vapor for 2 hours only, 2 hours daily for 1 week, and 2 hours daily for 3 weeks ; 4000 ppm of toluence vapor for 2 hours only and 2 hours daily for 1 week. For all these five groups, a 0.02 m3; whole body exposure chamber was used. Spin echo and field echo (FE, gradient echo) MR images were obtained at 0.5 T, and then histopathologic examination of the brain was performed. MR signal changes were statistically assessed for contrast to noise ratio (CNR). RESULTS: On T2-weighted MR images, the toluene-inhalation groups revealed diffuse hypointensity in the corpus striatum and thalamus, and diffuse hyperintensity in cerebral white matter, with statistically significant CNR change, compared with the control group. On T1-weighted and FE images, CNR differences in the corpus striatum, thalamus and cerebral white matter between the toluene inhalation groups were not statistically significant. Histopathologic study of these groups showed (1)neuronal degeneration such as shrinkage of neuronal cells and increase of the number of autophagosomes, (2)myelin degeneration and regeneration, and (3)focal axonal degeneration, In groups in which toluene inhalation was at higher concentrations and for longer, these phenomena were more extensive. CONCLUSION: As seen on MRI, toluene inhalation changes the signal intensity of the corpus striatum, the thalamus, and cerebral white matter. Neuronal, myelinic and axonal degeneration probably contribute to these signal changes.
Animals ; Axons ; Brain* ; Corpus Striatum ; Inhalation ; Magnetic Resonance Imaging* ; Myelin Sheath ; Neurons ; Noise ; Rats* ; Rats, Sprague-Dawley ; Regeneration ; Thalamus ; Toluene*

A statistical observation was made on 841 cases of urolithiasis among the l.004 cases which were seen during the 15 years period from January 1963 to December. 1977. 1. The incidence of the patients with urolithiasis was 1.85 % of total urological patients and 19.2 % of the inpatients. 2. The incidence of the patients with urolithiasis did not increase in spite of increasing annual incidence of inpatients. 3. They consisted of 266 patients with kidney stone (29 %) . 573 patients with ureter stone (61 %). 68 patients with bladder stone (7%) .and 26 patients with urethral stone (3%) The ratio of upper urinary tract stones to lower urinary tract stones was 9 to I. Among the 266 cases of the kidney stone, 21 cases were staghorn calculi. 4. The most favored predilection of ureter stones was lower 1/3 of ureter in 61% of these. 5. Seasonal variation of urolithiasis was not distinct, but the summer was the most favored season. 6. They were most commonly found between the ages of 20 to 50 (82 %). The causes were not found in all cases of childhood urolithiasis ( 8 cases) under the ages of 10. 7. The ratio of males to females was 2.7 to 1, however, the staghorn calculi were more commonly found in female. The ratio of males to females under age of 25 years was 1.8 to 1. 8. The upper urinary tract calculi occurred both in the right and left side with approximately equal frequency. 9. Multilocated stones were found in 10.7 % of all cases and bilateral stones were found in the 8.4% of the all cases. 10. The clinical symptoms of upper urinary tract calculi were flank pain in 85%, hematuria in 27.7 %, frequency in 17.8 %, nausea and vomiting in 10.4 %, and fever in 7.2%. The clinical symptoms of lower urinary tract calculi were painful urination in 78.7%, frequency in 48.8%, hematuria in 33%, and sudden stoppage in 33%. 11. The microscopic hematuria was found in 68.2% and pyuria in 47.7%. 12. Treatment consisted of surgical intervention in 70.3%, rnknown or expectant therpay in 14.4%, spontaneous expelling in 8.5%, and instrumental manipulation in 6.9%. 13. Definite histor of recurrent calculi was found in 27 cases (3.2%) and average duration of recurrence was 2.5 years.
Calculi ; Female ; Fever ; Flank Pain ; Hematuria ; Humans ; Incidence ; Inpatients ; Kidney Calculi ; Male ; Nausea ; Pyuria ; Recurrence ; Seasons ; Ureter ; Urinary Bladder Calculi ; Urinary Calculi ; Urinary Tract ; Urination ; Urolithiasis* ; Vomiting

A clinical and statistical observation was made on out-patients and in-patients admitted to the Department of Urology, Seoul National University Hospital for the past 24 years from 1954 to 1977. The observations were summarized as follows. 1. During the period, the total number of out-patients was 63,438 and that of in-patients, 6,028. 2. In the out-patients, lower urinary tract infections such as urethritis and prostatitis were the most common diseases regardless of the time period. 3. In the in-patient, the frequency of the disease has been changed with the lapse of time in the order of the occurrence. The interesting changes of the disease order related to the time period were noted as follows. 1954-1960 : genitourinary tuberculosis, urolithiasis, tumor, injury and congenital anomaly. 1961-1970 : urolitiasis, tumor, genitourinary tuberculosis, injury, infection and congenital anomaly. 1971-1977 : tumor. urolithiasis, genitourinary tuberculosis, congenital anomaly, injury and infection. 4. In 1977, 10 major diseases were tumor, ureteral stone, infertility, renal tuberculosis, B. P. H. hypospadias, varicocele, renal stone, scrotal injury and renal tumor 5. Major operations were performed on 4,122 cases during the period. Nephrectomy and ureterolithotomy were the most common operations. Recently, total cystectomy with ileal loop diversion, transurethral procedure and vasovasostomy, which require more skillful techniques, are increasing in number.
Cystectomy ; Female ; Humans ; Hypospadias ; Infertility ; Male ; Nephrectomy ; Outpatients ; Prostatitis ; Seoul* ; Tuberculosis ; Tuberculosis, Renal ; Ureter ; Urethritis ; Urinary Tract Infections ; Urolithiasis ; Urology* ; Varicocele ; Vasovasostomy