Relationships between tongue motility, grip force, and survival in SOD1-G93A rats.

Most preclinical studies of amyotrophic lateral sclerosis (ALS) have focused on spinal symptoms, despite the importance of bulbar deficits in progression of the disease. We sought to determine how bulbar deficits are related to spinal deficits and survival in the SOD1-G93A rat model of ALS. We examined forelimb and hindlimb grip force and tongue motility in SOD1-G93A rats using statistical cluster analysis.

Measures of bulbar and spinal motor function, muscle innervation, and mitochondrial function in ALS rats.

Symptom onset in amyotrophic lateral sclerosis (ALS) may occur in the muscles of the limbs (spinal onset) or those of the head and neck (bulbar onset). Most preclinical studies have focused on spinal symptoms, despite the prevalence of and increased morbidity and mortality associated with bulbar disease. We measured lick rhythm and tongue force to evaluate bulbar disease in the SOD1-G93A rat model of familial ALS.

D1 and D2 dopamine receptor expression is regulated by direct interaction with the chaperone protein calnexin.

As for all proteins, G protein-coupled receptors (GPCRs) undergo synthesis and maturation within the endoplasmic reticulum (ER). The mechanisms involved in the biogenesis and trafficking of GPCRs from the ER to the cell surface are poorly understood, but they may involve interactions with other proteins. We have now identified the ER chaperone protein calnexin as an interacting protein for both D(1) and D(2) dopamine receptors.