PGE2 Regulates Pacemaker Currents through EP2-Receptor in Cultured Interstitial Cells of Cajal from Murine Small Intestine

The interstitial cells of Cajal (ICCs) are the pacemaker cells in gastrointestinal tract and generate electrical rhythmicity in gastrointestinal muscles. Therefore, ICC may be modulated by endogenous agents such as neurotransmitter, hormones, and prostaglandins (PGs). In the present study, we investigated the effects of prostaglandins, especially PGE2, on pacemaker currents in cultured ICCs from murine small intestine by using whole-cell patch clamp techniques. ICCs generated spontaneous slow waves under voltage-clamp conditions and showed a mean amplitude of -452+/-39 pA and frequency of 18+/-2 cycles/min (n=6). Treatments of the cells with PGE2 (1muM) decreased both the frequency and amplitude of the pacemaker currents and increased the resting currents in the outward direction. PGE2 had only inhibitory effects on pacemaker currents and this inhibitory effect was dose-dependent. For characterization of specific membrane EP receptor subtypes, involved in the effects of PGE2 on pacemaker currents in ICCs, EP receptor agonists were used: Butaprost (1muM), EP2 receptor agonist, reduced the spontaneous inward current frequency and amplitude in cultured ICCs (n=5). However sulprostone (1muM), a mixed EP1 and EP3 agonist, had no effects on the frequency, amplitude and resting currents of pacemaker currents (n=5). SQ-22536 (an inhibitor of adenylate cyclase; 100muM) and ODQ (an inhibitor of guanylate cyclase; 100muM) had no effects on PGE2 actions of pacemaker currents. These observations indicate that PGE2 alter directly the pacemaker currents in ICCs, and that the PGE2 receptor subtypes involved are the EP2 receptor, independent of cyclic AMP- and GMP-dependent pathway.

Four Cases of Paramedian Thalamopeduncular Artery Infarction

Cerebral infarction in the territory of the paramedian thalamopeduncular artery (PTA) causes various lesions in the upper midbrain and thalamus resulting in widespread disturbances in neurological function. However, the exact topography and variations in the territories of the PTA remain unknown. We report four patients with MRI-proven infarctions in the PTA territory. One patient had lesions in the unilateral thalamus and midbrain, the other two had lesions in the bilateral paramedian thalamus and unilateral midbrain, and the remaining patient had lesions in the unilateral thalamus and bilateral midbrain. Clinical manifestations depended on the variations of the size and extent of infarctions. Theanatomical variations of the PTA are discussed and suggested.

Two Cases of Primary Progressive Aphasia

Primary progressive aphasia (PPA) is an uncommon neurodegenerative syndrome characterized by a progressive deterioration of language, while nonverbal cognitive and other neurological functions of PPA are relatively preserved for a longer period. However, it still remains unclear whether PPA represents a distinct diagnostic entity or a precursor of global dementia syndrome. We report PPA cases that presented with a slowly progressive language dysfunction without disturbing other daily living activities for several years. Repeated neuropsychological tests revealed progres-sive deterioration of executive aspects of language and mild memory dysfunction, although their receptive language and nonverbal cognitive functions were relatively preserved. The imaging of the brain showed prominent atrophic changes in the left perisylvian and the adjacent temporal region. In considering the mild cognitive decline accompanied by language deterioration, we conclude that in these cases it is clinically heterogenous and may be parts of a spectrum of focal forms of non-Alzeimer type dementia.

The Measurement of Bone Mineral Density in Parkinson's Disease

BACKGROUND: Osteoporosis, one of the most common metabolic bone disease, might be influenced by the severity of Parkinson's disease (PD). Objectives : We investigated the relationship between the Bone Mineral Density (BMD) and the severity of PD in postmenopausal and senile women. METHODS: We measured BMD of lumbar spine (L1-L4) by Dual energy X-ray absorptiometry (DEXA; Hologic QDR-4500A). We compared BMD between patient group (30 patients with PD) and control (183 postmenopausal and senile health women). The patients were divided into two groups according to osteoporosis and analyzed the following potential factors influencing BMD in PD; age, duration of symptom, age of onset, Hoehn and Yahr stage (H-Y stage), UPDRS motor score, duration of treatment, body mass index (BMI), dominant symptom such as tremor or rigidity. RESULTS: 1. BMD was significantly decreased with aging (p 0.05). CONCLUSION: Osteoporosis is related to H-Y stage, UPDRS motor score and BMI as well as aging in PD.