Chronic administration of pramipexole may also result in desensitization of D3 autoreceptors, leading to reduced dopamine transporter function, "We show that prolonged administration of pramipexole (0.1mg/kg/day, 6 to 21 days) [equivalent to a low ~0.5 mg/day human dose], a preferential D3R agonist, leads to a decrease in DA [dopamine] uptake in mouse striatum that reflects a reduction in DAT [dopamine transporter] affinity for DA in the absence of any change in DAT density or subcellular distribution ... These observations provide novel insights into the long-term antiparkinson, antidepressant and additional clinical actions of pramipexole and other D3R agonists".As summarized in the following commentary, trials have shown mixed results, "Dopamine agonists, such as pramipexole—a relatively selective dopamine D3 receptor agonist—are thus potential treatments for depression, especially anhedonic depression. D3 receptors are found in the mesolimbic system, which in turn has been implicated in the motoric and hedonic deficits in depression ... The first randomized controlled trial in patients with non-treatment-resistant major depressive disorder, by Corrigan et al., evaluated three dosages of pramipexole. The lowest dosage (0.375 mg/day) did not differentiate from placebo. The efficacy of the highest dosage (5.0 mg/day) was not evaluable, because of a 58% attrition rate. The third dosage (1.0 mg/day) was more effective than placebo ... Cusin et al. compared adjunctive adjunctive pramipexole with placebo in an 8-week randomized double-blind trial with 60 outpatients with major depression for whom at least one adequate antidepressant medication trial (mean, two trials) had failed.
Signs and symptoms that may be seen in acidosis include headaches, confusion, feeling tired, tremors, sleepiness, flapping tremor, and dysfunction of the cerebrum of the brain which may progress to coma if there is no intervention. Metabolic acidosis
Metabolic acidosis may result  from either increased production of metabolic acids, such as lactic acid, or disturbances in the ability to excrete acid via the kidneys, such as either renal tubular acidosis or the acidosis of kidney failure, which is associated with an accumulation of urea and creatinine as well as metabolic acid residues of protein catabolism. An increase in the production of other acids may also produce metabolic acidosis. For example, lactic acidosis may occur from:

severe (PaO2 <36mm Hg) hypoxemia causing a fall in the rate of oxygen diffusion from arterial blood to tissues. hypoperfusion (e.g., hypovolemic shock) causing an inadequate blood delivery of oxygen to tissues.A rise in lactate out of proportion to the level of pyruvate, e.g., in mixed venous blood, is termed "excess lactate", and may also be an indicator of fermentation due to anaerobic metabolism occurring in muscle cells, as seen during strenuous exercise. Once oxygenation is restored, the acidosis clears quickly. Another example of increased production of acids occurs in starvation and diabetic ketoacidosis. It is due to the accumulation of ketoacids (via excessive ketosis) and reflects a severe shift from glycolysis to lipolysis for energy needs.