{'fraction_non_alphanumeric': 0.033112582781456956, 'fraction_numerical': 0.009933774834437087, 'mean_word_length': 4.928104575163399, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Effects of beta-funaltrexamine (beta-FNA) on morphine dependence in rats and monkeys.

The opioid mu receptor antagonist beta-funaltrexamine (beta-FNA) blocked the development of physical dependence in rats when infused simultaneously with morphine for 6 days. In addition, beta-FNA given s.c. 24 h prior to the initiation and on day 3 of a 6 day period of morphine infusion in rats reduced the development of physical dependence in a dose-dependent manner. In morphine-dependent rhesus monkeys, beta-FNA precipitated a prompt and long-lasting withdrawal, which was not reversed within 30 h by subsequent injections of morphine. In contrast, naloxone-induced withdrawal lasted approximately 90 min. These results provide further evidence that beta-FNA is a long-acting antagonist of the opioid mu receptor, and that this receptor has a major role in the development of morphine-induced physical dependence.