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To clarify species differences in the pharmacokinetic parameters of cytochrome P450 (CYP) activities between humans and experimental animals, we assessed several CYP activities in mice, rats, dogs, monkeys, and microminipigs, using the simultaneous administration of typical human CYP substrates, such as caffeine (human CYP1A2 substrate), losartan (CYP2C9), omeprazole (CYP2C19), dextromethorphan (CYP2D6), and midazolam (CYP3A), to these animals. The intrinsic clearance (CLint) of these 5 substrates was also examined using the liver microsomes of humans and the experimental animals. The high bioavailabilities (BAs) and low CLint values of caffeine in the experimental animals were similar to those in humans. Mice and monkeys had lower BAs and higher CLint values of losartan than those in humans. Mice, rats, and monkeys had lower BAs and higher CLint values of omeprazole than those in humans. The lowest BAs of dextromethorphan were observed in monkeys and microminipigs, and only the CLint in dogs was similar to that in humans. The BA of midazolam in microminipigs only was similar to that in humans, while the CLint values in the other animals were similar to that in humans. These results indicated that in vitro and in vivo experimental data obtained using multiple animals including microminipigs are useful for predicting human pharmacokinetics.

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Adelie penguin colonies were surveyed throughout ice-free areas in Amundsen Bay, Enderby Land, from a helicopter on 23 December 1998. The locality and number of breeding pairs of three newly discovered colonies, in addition to a known colony are described. In total, about 9760 pairs of Adelie penguins breed in the four colonies in this region, comprising one of the largest breeding populations in eastern Enderby Land.

Adsorption characteristics of an anti-peptide antibody, obtained by immunization of eight amino acids in the C-terminal region of chimeric alpha-amylase of rice alpha-amylase isozymes, were studied by use of the chimeric enzyme and the peptide used for immunization. This anti-peptide antibody adsorbed the enzyme, as well as the peptide antigen, with sufficient affinity for immunoaffinity purification and was used for purification of the enzyme secreted from yeast cells. Chimeric alpha-amylase was purified by immunoaffinity chromatography to high purity in one step from the fermentation broth. One-third of the secreted enzyme was not adsorbed by the column of anti-peptide antibody because of processing in the C-terminal region.

Ahnak1, a giant 700 kDa protein, has been implicated in Ca(2+) signalling in various cells. Previous work suggested that the interaction between ahnak1 and Cavbeta(2) subunit plays a role in L-type Ca(2+) current (I (CaL)) regulation. Here, we performed structure-function studies with the most C-terminal domain of ahnak1 (188 amino acids) containing a PxxP consensus motif (designated as 188-PSTP) using ventricular cardiomyocytes isolated from rats, wild-type (WT) mice and ahnak1-deficient mice. In vitro binding studies revealed that 188-PSTP conferred high-affinity binding to Cavbeta(2) (K (d) approximately 60 nM). Replacement of proline residues by alanines (188-ASTA) decreased Cavbeta(2) affinity about 20-fold. Both 188-PSTP and 188-ASTA were functional in ahnak1-expressing rat and mouse cardiomyocytes during whole-cell patch clamp. Upon intracellular application, they increased the net Ca(2+) influx by enhancing I (CaL) density and/or increasing I (CaL) inactivation time course without altering voltage dependency. Specifically, 188-ASTA, which failed to affect I (CaL) density, markedly slowed I (CaL) inactivation resulting in a 50-70% increase in transported Ca(2+) during a 0 mV depolarising pulse. Both ahnak1 fragments also slowed current inactivation with Ba(2+) as charge carrier. By contrast, neither 188-PSTP nor 188-ASTA affected any I (CaL) characteristics in ahnak1-deficient mouse cardiomyocytes. Our results indicate that the presence of endogenous ahnak1 is required for tuning the voltage-dependent component of I (CaL) inactivation by ahnak1 fragments. We suggest that ahnak1 modulates the accessibility of molecular determinants in Cavbeta(2) and/or scaffolds selectively different beta-subunit isoforms in the heart.