The new angiotensin II (Ang II) receptor subtype blocker (AT₁ receptor blocker) has been clinically used as an antihypertensive agent. However the actions of AT₁ receptor blocker on myocyte hypertrophy in neonatal spontaneous hypertensive rat (SHR_Izm) and WKY_Izm are not fully understood. The purposes of this study were to investigate the differences in Ang II-induced myocyte hypertrophy between SHR and WKY, and which action of AT₁ or AT₂ receptor blocker is related to it's induction.
Cardiac myocytes were prepared from the heart of neonatal SHR and WKY, and cultured in serum-free medium for 10 days. From the 2nd day of culture, Ang II was added to the culture medium. AT₁ (CV-11974) or AT₂ (PD-123319) receptor blocker, L type calcium channel blocker (nisoldipine), calmoduline antagonist (W-7), and protein kinase C (PKC) inhibitor (staurosporine) were added to the culture medium containing Ang II (10^-8M). To assess cellular growth, cells were monitored with a video camera, and the area of the myocyte was measured using the video-micrometer system (VM-30, Olympus Co., Ltd.). BrdU uptake to DNA and colorimetric assay (MTT) for mitochondria were analyzed by ELISA reader.
The results were as follows: 1) The areas of myocyte under Ang II were greater in SHR (4172 μm²) than WKY (2270 μm²). 2) Both BrdU uptake and the activity of dehydrogenase (MTT assay) were increased in SHR compared to WKY. 3) Staurosporine, CV-11974 and nisoldipine significantly suppressed the Ang II-induced hypertrophy, whereas W-7 and PD-123319 failed to suppress it.
In conclusion, the cellular signals of Ang II -induced hypertrophy were upregulated. Also DNA synthesis and the activity of the hypertrophied cells were augmented in SHR, compared to WKY. These signals are transduced into the cell chiefly through AT₁ receptor. The effect of AT₂ receptor does not neccessarily counteract cellular growth through the AT₁ receptor. PKC-dependent, rather than calcium-dependent signals seem to be critical in Ang II-induced cellular growth in SHR.

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We investigated the excretion of thiamazole, an antithyroid drug, in the milk of 6 mothers with Graves' disease. Thiamazole in serum or milk was determined by high performance liquid chromatography. The mothers had been taking thiamazole 5-10 mg/ day, before and after delivery. The drug concentration in serum was almost equal to that in milk; it reached maximum at about 2 hours after the previous administration and was considerably decreased at 12 hours. The babies were breast-fed at 12 hours or more after the previous administration, and the drug was not detected (below about 1 ng/ml) in the serum of any baby. Thyroid function test results were normal in all babies.
These findings suggest that breast-feeding mothers with hyperthyroidism can continue thiamazole treatment, though further study is needed for assessment of safety, regarding the accumulation of the drug in the thyroid of babies.

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Using a questionnaire, we investigated the attitudes of pharmacists and medical representatives (MRs) towards drug interactions in daily practice. We received replies from pharmacists of 79 pharmacies and MRs of 27 pharmaceutical companies. The following results were obtained: 1) It is not rare for pharmacists to actually encounter prescriptions that can cause harmful drug interactions in daily practice. 2) However, 44% of the pharmacists have not decided precisely how to handle with such prescriptions. 3) Of the pharmacists, 44% give information about drug interactions to physicians. 4) About 70% of the MRs give more information about drug interactions to physicians and pharmacists than before. 5) About 60% of the pharmaceutical companies have prepared booklets or leaflets about drug interactions, however, there is still need for improvement of the contents. These results indicate that it is necessary for pharmacists, and pharmaceutical companies and their MRs to provide physicians with more and better information about drug interactions and to take concrete measures to cope with the prescriptions that can cause harmful drug interactions in daily practice.

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