PDGFR platelet-derived growth factor receptor
PDHC pyruvate dehydrogenase complex
PDI protein-disulphide isomerase
PECAM-1 platelet endothelial cell adhesion molecule 1
PEG polyethylene glycol
PEPCK phosphoenolpyruvate carboxykinase
PET positron emission tomography
PFC prefrontal cortex
PFK phosphofructokinase
PFL pyruvate-formate lyase
PG prostaglandin
PGE2 prostoglandin E2
PGF2 prostoglandin F2
PGG2 prostoglandin G2
PGI2 prostacyclin
PGK phosphoglycerate kinase
PGM phosphoglycerate mutase
PGS prostaglandin G/H synthase
PH pleckstrin-homology
PHAL Phaseolus vulgaris leukoagglutinin
Phe phenylalanine hydroxylase
PHF paired, helically wound, ~10 nm filament
PHGPx phospholipid hydroperoxide glutathione peroxidase
PHM peptidylglycine a-hydroxylatilng monooxygenase
PI phosphatidylinositol or phosphoinositide
Pi inorganic phosphate
PI 3-kinase phosphatidylinositol 3-kinase
PIP phosphatidylinositol 4-phosphate
PIP2 phosphatidyl-inositol 4,5-bisphosphate
PI-PLC phosphoinositide-specific phospholipase C
PKA protein kinase A or cAMP-dependent protein kinase
PKC protein kinase C or Ca++/diacylglycerol-dependent protein kinase
PKG protein kinase G or cGMP-dependent protein kinase
Pkr ds-RNA-activated protein kinase
PKU phenylketonuria
PLA phospholipase A
PLC phospholipase C
PLC-gamma phospholipase C gamma
PLD phospholipase D
PLP proteolopid protein
Pm promethium
PMA phorbol myristate acetate
PMCA plasma-membrane Ca++ pump
PMD Pelizaeus-Merzbacher disease
PML progressive multifocal leukoencephalopathy
PMP peripheral myeli protein
PMP-22 peripheral myelin protein 22
PNDA p-nitrosodimethylaniline
PNMT phenylethanolamine N-methyltransferase
PNS peripheral nervous system
Po polonium
pO2 local partial pressure for O2
PO2 partial pressure of oxygen
POBN alpha-(4-pyridyl 1-oxide)-N-tert-butylnitrone
POCT point of care testing
POMC proopiomelanocortin
POU conserved region in pit-1, oct-1, oct-2 and unc-86 proteins
PP1 protein phosphatase 1
PP2 protein phosphatase 2
PPADS pyridoxal phosphate-6-azophenyl-2',4'-disulfonic acid
Pr praseodymium
PRL prolactin
Pro proline
proANF proatrial natriuretic factor
PrP prion protein
PrPC prion protein cellular form
PrPSc prion protein scrapie form
PS phosthatidylserine or pregnenolone sulfate or presenilin
PSA polysialic acid
PSE portal-systemic encephalopathy
PSEP postsynaptic excitatory potential
PsmR presynaptic membrane receptor
PSP progressive suprenuclear palsy
PT pars tuberalis
Pt platinum
PTB phosphotyrosine binding domain
PTBR peripheral-type benzodiazepine receptor
PtdCho phosphatidylcholine
PtdEtn phosphatidylethanolamine
PtdGro phosphatidylglycerol
PtdGroPtd cardiolipin
PtdIns phosphatidylinositol
PtdIns 4,5P2 phosphatidylinositol 4,5-bisphosphate
PtdIns 4P phosphatidylinositol 4-phosphate
PtdOH phosphatidic acid
PtdSer phosphatidylserine
PTH parathyroid hormone
PTK protein tyrosine kinase
PTP protein tyrosine phosphatase
PTS-1 peroxisomal targeting signals (C-terminal)
PTS-2 peroxisomal targeting signals (N-terminal)
PTSD post-traumatic stress disorder
Pu plutonium
PUFA polyunsaturated fatty acid
PUVA psoralen-ultraviolet A
PVN paraventricular nucleus
PYK proline-rich tyrosine kinase
PZ pirenzepine
q theta
r rho
R gas constant
R+ photoactivated rhodopsin
Ra radium
RA rheumatoid artheritis
RACK receptors for activated protein kinase C
RAGE receptor for AGE
RAGS repulsive axon guidance signal
RAK delayed rectifier potassium channel
Rb rubidium
RCDP rhizomelic chondrodysplasia punctata
rCMRglc regional cerebral metabolic rate for glucose
rCNT nucleoside cotransporter
RDA recommended diatery allowance
Re rhenium
REM rapid eye movement
RER rough endoplasmic reticulum
RFI relative fluorescence intensity
RFLP restriction fragment length polymorphism
RGS regulators of G protein signaling
Rh rhodium
Rn radon
RNA ribose nucleic acid
RNase-L RNase-L
RNS reactive nitrogen species
ROP retinopathy of prematurity
ROS reactive oxygen species
RP retinitis pigmentosa
RPE retinal pigment epithelium
RPTK receptor protein tyrosine kinase
RQ respiratory quotient
RR ryanodine receptor calcium ion channel