W. Gibson Wood

Ethanol intoxication and withdrawal among three age groups of c57bl/6nnia mice.

Data have not been forthcoming on the effects of chronic ethanol administration on intoxication and severity of withdrawal using animals representative of the life-span of a particular species. The purpose of this study was to examine ethanol intoxication and withdrawal among three age groups (3, 14, 25 months) of C57BL/6NNIA male mice. Ethanol was administered in a liquid diet for 14 days. Pair-fed control groups and laboratory chow groups were also employed. Blood ethanol levels, signs of intoxication and withdrawal, liquid diet consumption, and body weight were measured. Old mice were significantly more intoxicated than younger mice. However, young mice consumed more ethanol as compared to the older mice. Blood ethanol levels did not differ among the three age groups, although variability was high within each age group. The ethanol liquid diet groups did not show a decrease in body weight. Withdrawal was more severe for old animals than younger animals. The greater effects of ethanol observed in the old animals do not appear to be attributable to age differences in blood ethanol levels, amount of ethanol consumed, or body weight loss.

Relationship of age and hypertension to neuropsychological test performance

Young adult (X- = 29) and middle aged (X- =50) hypertensive and normotensive subjects were compared with respect to seven neuropsychological test scores derived from tests on the Halstead-Reitan battery. Age main effects, with inferior performance for the middle aged subjects, were observed for the localization and time portions of the Tactile Performance Test (TPT) and for the Trail Making A test. The multivariate age effect was significant for the composite of seven scores. A multivariate blood pressure main effect was obtained and main effect blood pressure was significant for the category test; hypertensives made more errors than normotensives. A blood pressure by age interaction was observed for finger tapping scores and the TPT-Memory scores with larger differences between hypertensives and normotensives for the younger than for the middle aged group. Results were discussed in terms of previous studies of age and hypertension with the WAIS, the Primary Mental Abilities Test and serial reaction time measures. The poor prediction of hypertensive status from individual neuropsychological test scores was emphasized and readers were cautioned not to conclude that essential hypertensives, as a group, can be characterized as brain damaged.

Anxiety and depression in young and middle aged hypertensive and normotensive subjects.

This study examined the effects of essential hypertension on measures of anxiety and depression for two age groups of hypertensive (free from hypertension-related pathology and/or cardiovascular disease) and normotensive subjects. Hypertensive subjects had significantly higher State Anxiety scores and Zung Depression scores than did normotensive subjects. These differences between the blood pressure groups were due largely to the scores of the younger hypertensive subjects. The results of the present study are consistent with previous results from our laboratory that have found that younger hypertensives differed (relative to controls) from middle aged hypertensives on measures, such as, symptoms reported on the Cornell Medical Index and WAIS Performance scores. The results of the present study were discussed within the context of age associated differences in response to hypertension and factors that might account for these differences.

Facilitation by dexamethasone of tolerance to ethanol in the rat

The purpose of this study was to examine the relationship between the development of tolerance to ethanol and the hypothalamic-pituitary-adrenal cortex (H-P-AC) system by modifying the H-P-AC system through the use of a synthetic glucocorticoid, dexamethasone. Also this study determined whether repeated drug administration and environmental adaptation would facilitate development of tolerance. Rats injected daily with dexamethasone and ethanol showed an antagonism to the acute effects of ethanol and a higher rate of tolerance development to the depressant effect of ethanol than animals administered ethanol only. These results were discussed in relation to a possible stimulant effect of dexamethasone on behavior, an increase in the metabolism of ethanol, and a possible accumulation of dexamethasone in the brain, affecting an organisms response to ethanol. It also was shown that daily ethanol administration and adaptation to the testing environment facilitated the development of tolerance, compared to ethanol administration only.

Age-associated differences in response to alcohol in rats and mice. A biochemical and behavioral review.

The purpose of this review was an examination of the biochemical and behavioral literature on alcohol and aging. The biochemical literature indicated that older animals show differences in response to alcohol using metabolic measures such as: alcohol dehydrogenase, blood alcohol concentration, and acetaldehyde. However, these differences were not always in the predicted direction (i.e, a reduction with increasing age), suggesting that changes in these metabolic factors do not fully explain differences among age groups in response to alcohol. Behavioral data demonstrated that preference for alcohol was affected by the age of the animal and/or previous experience with the drug. Generally, alcohol preference decreases with advancing age, but this was dependent in a large part on the genotype of the animal and the concentration of alcohol used. Several methodological problems are apparent in the literature on age-related changes in response to alcohol (e.g., narrow range of ages used, inadequate dose-response curves and an absence of proper control groups). Ways of reducing these problems and directions for future research were discussed.

Ethanol preference in C57BL/6 and BALB/c mice at three ages and eight ethanol concentrations

Eight ethanol concentrations (4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%) were used. A reduction in ethanol preference with increasing age was seen in the C57BL/6 mice, but not in the BALB/c animals. For C57BL/6 mice the largest difference in ethanol preference occurred between the 10% and 18% ethanol solutions. It was found that the ethanol preference of the 14-16 mo. C57BL/6 mice was similar to the 7-9 mo. old C57BL/6 mice at the first 5 concentrations. For the remaining concentrations the 14-16 mo. mice more closely resembled the 22-24 mo. mice in ethanol preference. The results of this study suggested that increased age does not simply result in a reduction in ethanol preference, but is a function of the genotype and concentration of the ethanol solution.

The role of locomotion in conditioning methylphenidate-induced locomotor activity.

This experiment determined whether overt performance of the entire response (actual running) was necessary for the conditioning of methylphenidate-induced locomotor activity (wheel-running) in guinea pigs. Four guinea pigs were given daily injections of 2.5 mg/kg methylphenidate and were allowed to run in activity wheels; 4 other guinea pigs were given methylphenidate and were placed in locked activity wheels; a third group of 4 guinea pigs were administered saline and allowed to locomote; a fourth group of 4 guinea pigs received saline injections and were placed in locked activity wheels. After 12 days of injection, all animals were given saline injections on the 9 subsequent days and allowed to run freely in the wheels. The 2 groups which had received methylphenidate showed more locomotor activity than the saline injected animals but were not distinguishable from each other on the basis of prior opportunity to engage in locomotor activity. These results were interpreted to indicate that (a) increased methylphenidate-induced locomotor activity may be conditioned with repeated administration of the drug, and (b) actual running is not essential for the conditioning of drug-induced wheel-running.

Symptoms reported on the cornell medical index in relationship to hypertension and age

This study compared young and old hypertensive and normotensive subjects with respect to the number of symptoms reported on the Cornell Medical Index (CMI). The hypertensive subjects had more physical and psychological complaints than did the normotensive subjects. Differences in symptoms reported between the blood pressure groups were not concentrated in one specific category (e.g., cardiovascular) but were distributed over several categories. Age did not influence the number of symptoms reported for either blood pressure group. The results were discussed in the context of the lack of specificity of symptoms reported by hypertensive subjects, and to what extent reported symptoms on the CMI are influenced by knowledge of ones blood pressure status.

The Elderly Alcoholic: Some Diagnostic Problems and Considerations

The purpose of this chapter is to discuss some of the problems associated with the diagnosis of alcoholism2 in the elderly. This is an area that has received little attention both clinically and with regard to research. Thus, there are no easy answers for the clinician who must identify and treat the elderly alcoholic. Thus, this chapter is designed to increase the clinicians awareness of the problem and to point to some of the specific issues associated with alcoholism in the elderly.