technetium-tc-99m-bicisate and Hypertension

We evaluated the effects of olmesartan, an angiotensin II receptor blocker (ARB), on cerebral blood flow (CBF) in elderly and hypertensive subjects. Ten subjects with first- or second-degree essential hypertension (mean age, 70.5 years) underwent brain single-photon emission tomography (SPECT) scanning with (99m)Tc-ethyl cysteinate dimer before and after a 24-week course of olmesartan. Mean systolic blood pressure (SBP) was 156.2+/-9.9 mm Hg, and mean diastolic blood pressure (DBP) was 89.1+/-5.5mm Hg. No subject had any abnormalities on neurologic examination or previous history of stroke or cardiovascular disease. Before olmesartan administration, the hypertensive subjects had approximately 15% less whole brain CBF compared with age-matched normotensive controls. Regional CBF was decreased by 11%-20% in the frontal, parietal, temporal, and posterior lobes. Olmesartan treatment significantly decreased SBP to 130.4+/-4.2mm Hg (P < .001) and DBP to 78.2+/-7.0mm Hg (P < .001). After 24 weeks of olmesartan treatment, CBF of whole brain and regional CBF of the frontal, parietal, and temporal lobe were similar to those of control subjects. Our brain SPECT data indicate that olmesartan restores brain hypoperfusion in elderly and hypertensive patients without organic damage. This ARB may have a favorable potential for cerebrovascular circulation, in addition to a blood pressure-lowering effect.

Topics: Aged; Aged, 80 and over; Angiotensin II Type 1 Receptor Blockers; Antihypertensive Agents; Blood Pressure; Brain; Cerebrovascular Circulation; Cysteine; Female; Humans; Hypertension; Imidazoles; Magnetic Resonance Imaging; Male; Organotechnetium Compounds; Tetrazoles; Tomography, Emission-Computed, Single-Photon

Experienced practitioners of yoga have been shown to alter brain function, but this case series measured cerebral blood flow before and after a 12-week training program in Iyengar yoga (IY) for naïve subjects.. On the first day, each of the 4 subjects listened to the teacher speaking on the history and background of the yoga program while they were injected with 250 MBq of (99m)Tc-bicisate and received a single photon emission computed tomography scan (pre-program baseline). Subjects then had their first IY training and were injected and scanned with 925 MBq bicisate while they did their first meditation (pre-program meditation). Subjects then underwent a 12-week training program in IY and then underwent the same imaging protocol with a postprogram baseline and postprogram meditation scan. Baseline and meditation scans, before and after training, were compared using paired t tests.. There were significant decreases (p < 0.05) between the pre- and postprogram baseline scans in the right amygdala, dorsal medial cortex, and sensorimotor area. There was a significant difference (p < 0.05) in the pre- and postprogram percentage change (i.e., activation) in the right dorsal medial frontal lobe, prefrontal cortex, and right sensorimotor cortex.. These initial findings suggest the brain experiences a "training effect" after 12 weeks of IY training.

Topics: Adult; Brain; Cerebrovascular Circulation; Cysteine; Female; Humans; Hypertension; Male; Meditation; Middle Aged; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Yoga

Hypertension in an 83-year-old woman with early Alzheimer disease was treated with a calcium channel blocker, nilvadipine, for 3 months. Before and after nilvadipine treatment, global and regional cerebral blood flow (gCBF and rCBF) were measured using Tc-99m ethyl cysteinate dimer SPECT. This treatment elevated both the Mini-Mental State Examination score from 23 to 27 and gCBF from 37.6 to 42.0 mL/100 g/min. This treatment also elevated rCBF prominently in the bilateral frontal cortex, right parietal cortex, and posterior cingulate cortex. These areas with rCBF increase generated by subtraction of pretreatment SPECT from post-treatment SPECT were demonstrated on a coregistered MRI.

Topics: Aged, 80 and over; Alzheimer Disease; Antihypertensive Agents; Cerebrovascular Circulation; Cysteine; Female; Humans; Hypertension; Nifedipine; Organotechnetium Compounds; Radiopharmaceuticals; Regional Blood Flow; Tomography, Emission-Computed, Single-Photon