Journal: Cell Reports Medicine
Article Title: Role of dopamine in the development of impaired counterregulation and impaired awareness of hypoglycemia
doi: 10.1016/j.xcrm.2026.102710
Figure Lengend Snippet: Sympathoadrenal response and dopaminergic action with agonist bromocriptine (A–C) Recurrent BROMO administration in i.c.v. reduced food intake and BG response. (A) Schematic diagram of recurrent aCSF ( n = 7) or recurrent BROMO ( n = 7, 2 μg) for 3 days into i.c.v. (B) BG on day 4 following singular injection of INS (15 U/kg NPH) Groups were compared via two-way ANOVA. (C) Cumulative food intake after INS injection (∗ p < 0.005 RBROMO i.c.v. vs. RCSF i.c.v. + INS). Groups were compared via unpaired t test. Each bar represents the mean + SEM. (D–H) Recurrent BROMO administration in i.c.v. and effects on CRR. (D) Schematic diagram of recurrent aCSF ( n = 7) or recurrent BROMO ( n = 7, 2 μg) into i.c.v.. (E) BG during hyperinsulinemic-hypoglycemic clamp where BG is held at 40–45 mg/dL for 90 min. Groups were compared via two-way ANOVA. (F) Ginf. Rate during clamp (∗∗∗∗ p < 0.0001 vs. RBROMO). Groups were compared via unpaired t test. (G) Peak epinephrine concentrations at basal and hypoglycemia (∗ p < 0.005 RCSF vs. RBROMO). Groups were compared via two-way ANOVA. (H) Peak glucagon concentrations at basal and hypoglycemia (∗ p < 0.005 RCSF vs. RBROMO). Groups were compared via two-way ANOVA. Each bar represents the mean + SEM. (I) Dopaminergic gene expression in VTA. Relative gene product expression of COMT, DDC, DRD2, SLC6A3 in the ventral tegmental area following 3-day treatment with RS ( n = 6), RH ( n = 7), or RH + MET ( n = 6) (∗ p < 0.04 RS vs. RH + MET; # p < 0.04 RH vs. RH + MET). Groups were compared via one-way ANOVA. Each bar represents the mean + SEM. (J–O) Recurrent BROMO infusion in VTA effects on CRR. (J) Schematic diagram of recurrent aCSF ( n = 7) or recurrent BROMO (n = 7–9, 5 μg/day; infusion rate 0.1 μL/min). (K) BG concentration during hyperinsulinemic-hypoglycemic clamp, which held BG at 40–50 mg/dL for 90 min. Groups were compared via two-way ANOVA. (L) Ginf. rate during clamp (∗∗∗∗ p < 0.001 RCSF vs. RBROMO). Groups were compared via two-way ANOVA. (M) Peak epinephrine concentrations at basal and hypoglycemia (∗ p < 0.05 BROMO vs. SAL). Groups were analyzed via unpaired t test. (N) Relative gene expression of DRD2 in the ventral tegmental area following a 3-day treatment with either aCSF or BROMO directly into the VTA (∗ p < 0.05 aCSF vs. BROMO). Groups were compared via unpaired t test. (O) Relative gene expression of SLC6A3 in the ventral tegmental area following a 3-day treatment with either aCSF or BROMO directly into the VTA ( p = 0.21). Groups were compared via unpaired t test. Each bar represents the mean + SEM.
Article Snippet: In brief, total RNA was extracted and purified from brain regions using miRNeasy Mini Kit (Qiagen, CA) which was reverse transcribed and then amplified by real-time PCR using Taqman gene assays (Thermo Fisher) for dopamine receptor D2 ( Drd2 ; assay ID: Rn00561126_m1), dopamine transporter or solute carrier family 6, member 3 ( Dat or Slc6a3 ; assay ID: Rn00562224_m1), dopa decarboxylase ( Ddc : assay ID: Rn01401189_m1), catechol- O -methyltransferase ( Comt ; assay ID: Rn00561037_m1) and the housekeeping gene beta-actin ( Actb ; assay ID: Rn00667869_m1).
Techniques: Injection, Gene Expression, Expressing, Concentration Assay