Spatial and temporal patterns in summer ichthyoplankton assemblages on the eastern Bering Sea shelf 1996-2007.

Larval and early juvenile fishes were sampled from the eastern Bering Sea (EBS) shelf from 2001 to 2005, and in 2007. Data from these collections were used to examine spatial and temporal patterns in species assemblage structure and abundance. The years 2001-2005 were unusual because the EBS water temperature was 'warm' compared with the long-term mean temperature.

Human cardiac phospholipase D activity is tightly controlled by phosphatidylinositol 4,5-bisphosphate.

Phospholipase D (PLD) plays a central role in receptor-mediated breakdown of choline phospholipids and formation of phosphatidic acid (PA), an important regulator of cardiac function. However, specific mechanisms that regulate myocardial PLD activity remain largely unknown, particularly in the human heart. We hypothesized that phosphatidylinositol 4,5-bisphosphate (PIP2), best known as substrate for phospholipase C (PLC) isozymes, plays a critical role in regulating myocardial PLD activity.

Adrenergic activation of cardiac phospholipase D: role of alpha(1)-adrenoceptor subtypes.

Objective: Adrenergic stimulation of the heart leads to activation of the phospholipase D signal transduction pathway with formation of the intracellular second messengers phosphatidic acid and diacylglycerol, which may play a role in the development of myocardial hypertrophy by activating mitogen-activated protein kinases and protein kinase C. So far, the adrenergic receptor subtypes mediating activation of cardiac phospholipase D are not known.

Methods: We developed an assay for determination of phospholipase D activity in the isolated perfused rat heart.

A HPLC-fluorescence detection method for determination of cardiac phospholipase D activity in vitro.

A nonradioactive assay for the investigation of phospholipase D (PLD) activity in cardiac membranes has been developed. A fluorescent derivative of phosphatidylcholine [2-decanoyl-1-(O-(11-(4,4-difluoro-5,7-dimethyl-4-bora-3a, 4a-diaza-s-indacene-3proprionyl)amino) undecyl) sn-glycero-3-phosphocholine] was utilized as substrate in an in vitro PLD-catalyzed transphosphatidylation reaction utilizing ethanol as second substrate. Unreacted phosphatidylcholine and the products of phospholipase activity (PEtOH, phosphatidylethanol; PA, phosphatidic acid; DAG, diacylglycerol) were separated by a binary gradient HPLC system and detected by fluorometry.