Science - 06.03.2020

Kataokaet al.,Science 367 , 1105–1112 (2020) 6 March 2020 3of8

Injection

Saline

Muscimol

Injection

–1.0

–0.5

0

0.5

1.0

1.5

2.0

2.5

–60 –30 0 30 60 90 120

Δ

Tcore

(°C)

Time (min)

Injection

**

Muscimol

• 
  
  
  
  • 
    
  
  
  
  

ΔT

core

AUC (°C·min)

E F

–1.0

–0.5

0

0.5

1.0

1.5

2.0

2.5

–60 –30 0 30 60 90

ΔT

BAT

(°C)

Time (min)

Injection

120

**

ΔT

BAT

AUC (°C·min)

C D

Muscimol

• 
  
  
  
  • 
    
  
  
  
  

–1.0

–0.5

0

0.5

1.0

1.5

2.0

2.5

–60 –30 0 30 60 90 120

Time (min)

Injection

ΔT

core

(°C)

–1.0

–0.5

0

0.5

1.0

1.5

2.0

2.5

–60–300 306090120

Δ

TBAT

(°C)

Time (min)

Injection

ΔT

BAT

AUC (°C·min)

• 
  

I J

Muscimol

• 
  
  
  
  • 
    
  
  
  
  

IL

0

p=0.24

Muscimol

• 
  
  
  
  • 
    
  
  
  
  

Δ

Tcore

AUC (°C·

min)

K L

Nv

IL

DTT

DP

Bregma +2.5 mm

IL

DP

DTT

G H

Nv

IL

DTT

DP

Bregma +2.5 mm

IL

DP

DTT

Nv

A B

DP/DTT

0

10

20

30

40

–60 –30 0 30 60 90

–10

Time (min)

120

0

200

400

600

800

1,000

1,200 **

Muscimol

• 
  
  
  
  • 
    
  
  
  
  

P Q

–50

0

50

100

150

200

–60 –30 0 30 60 90 120

Time (min)

2,000

4,000

6,000

8,000

*

0

NO

Muscimol

• 
  
  
  
  • 
    
  
  
  
  

Nv

IL

DTT

DP

Bregma

+2.5 mm

M DP/DTT

Saline

Muscimol

Saline

Muscimol

Saline

Muscimol

Saline

Muscimol

Δ

HR (bpm)

Δ

HR AUC (bpm·min)

ΔMA P(mm

Hg)

ΔMAP AUC (mmHg·min)

–20

0

20

40

60

80

100

120

–20

0

20

40

60

80

100

120

0

20

40

60

80

100

120

140

20

40

60

80

100

120

******

******

****** *

****** Saline ******

Muscimol

Fig. 2. Neurons in the DP/DTT, rather than the IL, mediate sympathetic stress
responses.(AtoQ) Effects of bilateral muscimol nanoinjections into the DP/DTT
[(A) to (F) and (M) to (Q)] or the IL [(G) to (L)] on SDS-evoked BAT thermogenesis
and hyperthermia [(A) to (L)] or cardiovascular responses [(M) to (Q)]. After
saline or muscimol injections [1 mM; (A) to (L): 200 nl per site, (M) to (Q): 100 nl per
site; marked by green microspheresin(A)and(G);scalebars,500mm] into the
DP/DTT [(A), (B), and (M)] or the IL [(G) and (H)] (the right side of the symmetric
bilateral injections is shown), animals were exposed to SDS [gray zones in (C),
(E), (I), (K), (N), and (P)]. All rats (n= 5 per group) underwent two stress trials,

1 week apart, with saline (first trial) and muscimol (second trial) injections at the
same sites. Time-course changes inTBAT,Tcore, HR, and MAP were analyzed by
repeated measures two-way analysis of variance (ANOVA) [(C): injectant:F1,4=19.85,

P= 0.011, time:F180,720=8.976,P< 0.001, interaction:F180,720=8.68,P<0.001;(E):

injectant:F1,4= 36.89,P= 0.004, time:F180,720=10.93,P<0.001,interaction:

F180,720=10.38,P< 0.001; (I): injectant:F1,4=22.5,P= 0.009, time:F180,720= 25.47,

P< 0.001, interaction:F180,720=4.63,P<0.001;(K):injectant:F1,4=0.35,P=

0.585, time:F180,720= 12.64,P<0.001,interaction:F180,720=2.07,P<0.001;(N):

injectant:F1,4=27.99,P=0.006,time:F180,720= 15.54,P<0.001,interaction:

F180,720=2.48,P<0.001;(P):injectant:F1,4= 55.59,P=0.002,time:F180,720= 11.16,

P< 0.001, interaction:F180,720=2.47,P< 0.001] followed by Bonferroni’sposthoc

test (red bars with asterisks indicate time points with significant differences). Area

under the curve (AUC) during the stress period was analyzed by pairedttest [(D):t 4 =

7.57; (F):t 4 = 5.93; (J):t 4 =3.46;(L):t 4 = 1.39; (O):t 4 =4.39;(Q):t 4 =6.92].*P<

0.05; **P< 0.01; ***P<0.001.ErrorbarsindicateSEM.bpm,beatsperminute.

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