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HORMONES AND HEART. More than a million Americans suffer heart attacks every year, the large majority of them men. In fact, the risk of heart attacks among middle-aged men is five times as great as among their female counterparts. Why? For many years doctors suspected that the higher levels of estrogens--the female sex hormones --in women somehow protected them against heart attacks. Reason: it is only after menopause, when estrogen production drops, that the incidence of heart attacks begins to rise among women. Now a Columbia University internist has found evidence that undermines this theory.

In a study published last week in the Proceedings of the National Academy of Sciences, Dr. Gerald Phillips reported that among male heart attack victims up to age 44, there is a pronounced increase in the blood levels of estradiol--one of the estrogens. But their levels of testosterone, the major male sex hormone, remain normal.

Phillips does not know why there was a change in the ratio of estradiol to testosterone in the heart attack victims, but his work has shown that the hormone imbalance is also related to other abnormalities frequently found in heart patients--higher-than-normal levels of blood cholesterol, fat, sugar and insulin. That finding, he said, appears to be "the elusive link between the mild form of diabetes and heart disease." If the hormonal imbalance is proved to be the root cause of heart disease, Phillips concluded, diet, drugs or other means might be used to change the blood hormone levels in order to prevent a heart attack.

ALCOHOLISM AND BRAIN. Is alcoholism caused by purely social or psychological factors, or does it have its origins in some quirk of body chemistry? Last week two Purdue University scientists published the results of an intriguing experiment that may help clarify the issue.

Neurobiologists Robert Myers and Christine Melchoir injected directly into the brains of laboratory rats a compound called tetrahydropapaveroline (THP), which is present in opium poppies and is used by the plant to manufacture morphine. Given a choice of drinking water or ethyl alcohol during the early stages of the experiment, the rats, which normally shun alcohol, always opted for the water. But, Myers and Melchoir write in Science, after only three days of THP treatment the teetotaling rats began switching to the sauce. Indeed, after a while the rodents became so addicted that they exhibited all the symptoms of alcoholism, including a rodent version of delirium tremens (DTs) characterized by whisker-twitching, jerking movements and "wet-dog" shakes.

These findings, says Myers, contradict a recent Rand Corp. study (TIME, June 21) that suggested some alcoholics could safely return to moderate drinking. He points out that even after nine months of abstention the rats preferred alcohol over water. This strongly bolsters his suspicion that alcoholism is due not to social conditioning--as the Rand study implied--but to lasting chemical changes in the brain. Still, Myers, who has also discovered a chemical that reduces alcohol consumption in addicted animals, holds out hope. If alcoholism is really rooted in brain chemistry, a drug treatment may be devised to help the problem drinker.

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