Relationships between mood and estradiol (E2) levels in Alzheimer's disease (AD) patients.

This study investigates the relationship between mood and estradiol (E2) levels and assesses the prevalence of mood symptoms in Alzheimer's disease (AD) patients compared to healthy elderly controls. Fifty-two AD patients (26 men, 23 estrogen non-using women and three estrogen-using women), mean age 76.2 years, were recruited and assessed with the Geriatric Depression Scale (GDS), a test of mood, and a radioimmunoassay measure of E2 levels at the time of testing. The AD patients were compared to a control group of age and gender-matched healthy elderly men and women estrogen-users and non-users. No differences were found between the AD patients and the controls in overall E2 levels, but, as expected, the women estrogen-users in both the AD and control groups had higher E2 levels than the men and the female estrogen non-users. Both groups of men had higher E2 levels than the estrogen non-using women. There was a significant negative correlation between E2 levels and GDS scores in the full sample, which was particularly strong in the estrogen-using women. This indicates that those subjects with higher E2 levels had less mood symptomatology. Overall, mood scores in the AD patients were higher than in the healthy controls, indicating higher levels of depressive symptomatology; the highest depression scores occurred in the AD women who were estrogen non-users. This suggests that depressive symptoms are common in AD patients, and that women with AD who are not taking estrogen replacement may be especially vulnerable to depression.

Relationships between dehydroepiandrosterone sulfate (DHEAS) and cortisol (CRT) plasma levels and everyday memory in Alzheimer's disease patients compared to healthy controls.

Fifty-two age-matched Alzheimer's disease (AD) patients (26 men, 26 women), mean age 76.2 years, were assessed with the Rivermead Behavioural Memory Test, a test of everyday memory, coincident with the measurement of plasma cortisol (CRT) and dehydroepiandrosterone sulfate (DHEAS) via radioimmunoassay. The AD patients were compared to a control group of age- and gender-matched healthy elderly men and women. No differences were found between the AD patients and the controls in DHEAS or CRT levels, or in the DHEAS/CRT ratio. There were no gender differences in DHEAS or CRT levels, or in the DHEAS/CRT ratio in subjects with AD. However, AD patients with higher levels of DHEAS scored better than those with lower levels on the subtests of Remembering a Name associated with a picture, Digit Span Total and Forward, and the Mini Mental Status Exam. AD patients with higher CRT levels performed worse on Delayed Route Recall than those with lower levels. These findings suggest that AD patients with higher endogenous levels of DHEAS may perform better on some memory tasks than those with lower levels, while AD patients with lower levels of CRT may perform better than those with higher CRT.

Interrelationships among wall structure, smooth muscle orientation, and contraction in human major cerebral arteries.

Human major cerebral arteries were fixed under pressure in the brain or after excision and ligation. They were sectioned and stained for light microscopy. Sterological point counting was used on mid-plane longitudinal sections of ten segments to determine that the media occupied 52.0% +/- 6.39 (SD) of the arterial wall and that the smooth muscle comprised 72.0% +/- 4.76 (SD) of the media. In arterial segments containing nine planar bifurcations, areas of varying muscle orientation and composition were identified and mapped out. A circumferential alignment of smooth muscle was consistently found in the cerebral branching systems except for the bifurcation region proximal to the apex at major bifurcations where the regular pattern was replaced by multilayered multidirectional smooth muscle. Theoretical models relating smooth muscle contraction to arterial caliber in cylindrical segments are outlined. In the extreme case of complete closure of an artery, our prediction is that for a typical cerebral arterial media the outermost muscle cells should have to contract to 42% of their relaxed length. The possible importance of medial smooth muscle patterns in the pathogenesis of cerebrovascular lesions is discussed.